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Guiney, 2012

Created By: Riley Quijano
Innovations and New Technology
For Improved Public Weather Services
John L. Guiney
Chief, Meteorological Services Division
NOAA/National Weather Service Eastern Region
Bohemia, New York  USA  11716
The emergence of new, innovative and technologically advanced forecast systems and communications
systems offers the opportunity to integrate public weather services dissemination and service delivery.
Digital database forecasting and next-generation workstations, along with new and emerging information
technology systems and applications, can significantly enhance and improve public weather services
provided by NMHSs.  [1]State-of-the-art Nowcast systems will integrate an array of real-time data and NWP
output to provide prognostic information while also helping to rapidly generate and disseminate forecast
  [2]Information technology systems and associated applications, including XML, CAP, and RSS, will
allow NHMSs to exploit the latest telecommunication networks, including broadband, wireless, and mobile
Coupled with GIS and GPS capabilities, NMHSs can satisfy customer and partner demands
forever increasing precision, accuracy, and detailed, location-specific hydrometeorological forecasts and
  [4]Together, these efforts will allow NMHSs to cultivate an innovative and effective PWS program
which leverages technological advances to create a holistic forecast and warning dissemination, service
delivery, and all-hazard decision support process that best serves the user community.

1. Introduction
New communication and forecast system innovations
communication, digital database forecasting, next-
generation workstations, Nowcasting systems) have
emerged which provide the opportunity to improve
public weather services (PWS).  These innovations allow
World Meteorological Organization (WMO) National
Meteorological/ Hydrometeorological Services (NMHSs)
to provide hydrometeorological forecasts and warnings
in a variety of formats (graphic, digital) beyond the
traditional text products.  In addition, these innovations
can impact NMHS service delivery capabilities.  Digital
database forecasting and next-generation workstations,
along with new and emerging Information Technology
(IT) systems and applications offer the opportunity to
further enhance and integrate PWS dissemination and
service delivery functions. 
This paper provides an overview of several key
innovations, technological advancements, and IT
systems/applications which are, or can, have a substantial
impact on improving NMHSs public weather services
and their dissemination and service delivery.  The paper
will focus on digital database forecasting, next-
generation forecast workstations, Nowcasting systems,
and IT systems and applications.
2. Digital Database Forecasting 
The traditional forecast process employed by most
NMHSs involved forecasters producing text-based
sensible weather element forecast products (e.g.,
maximum/minimum temperature, cloud cover) using
numerical weather prediction output as guidance.  The
process is typically schedule driven, product oriented,
and labor intensive.  Over the last decade, technological
advances and scientific breakthroughs have allowed
NMHS’s hydrometeorological forecasts and warnings to
become much more specific and accurate.  As computer
technology and high speed dissemination systems
evolved (e.g. the Internet), NWS customers/partners
were demanding detailed forecasts in gridded, digital,
and graphic formats.  Traditional NWS text forecast
products limit the amount of additional information that
can be conveyed to the user community.  The concept of
digital database forecasting provides the capability to
meet customer/partner demands for more accurate,
detailed hydrometeorological forecasts. Digital database
forecasting also offers one of the most exciting
opportunities to integrate PWS forecast dissemination
and service delivery, which most effectively serves the
user community. Both the NOAA/National Weather
Service and Environment Canada are currently using
digital database forecasting technology to produce
routine forecasts. The Australian Bureau of Meteorology
is in the process of evaluating and developing an
implementation plan for database forecasting using the
NOAA/National Weather Service National Digital
Forecast Database approach.  
Element Database  
Environment Canada (EC) has developed the National
Weather Element Forecast Database (NWEFD) that is
populated with the output from the EC numerical
weather prediction models. EC forecasters manipulate
the NWEFD making adjustments to forecast fields based
on an analysis of the current state of the atmosphere and
model output including known model biases and trends.
When complete, the forecaster runs software that creates
text-based forecasts.  To assist in the development and
population of the NWEFD, EC has developed an expert
system called SCRIBE.  
SCRIBE is an expert system capable of automatically or
interactively generating a wide array of weather products
for a region or a specific locality1.  The system uses data
from a set of matrices which are generated after the 00Z
and 12Z numerical weather prediction model runs. These
matrices contain different types of weather elements
including numerical weather prediction (NWP) output,
statistical guidance model output (Perfect Prog – PP and
Updateable Model Output Statistics – UMOS models),
and climatological data. SCRIBE’s temporal resolution is
3 hours.  SCRIBE produces forecasts twice daily for
1,145 Canadian station locations.  When ready, the
matrices are sent to each regional SCRIBE system. 
Upon arrival, the data is processed by the Concept
Generator and is synthesized and downsized to a set of
well defined weather elements called “concepts”.  These
concepts are output in a digitally-coded format called
METEOCODE and can be displayed on a graphic
interface. Forecasters can modify the concept output to
incorporate the latest observations as well as the
evolving weather scenario/event.  The concepts are used
by the regional offices to generate local forecast
products. The concepts will also be sent to the NWEFD
where a suite of national forecast products are generated. 
Figure 1 shows the main steps in the SCRIBE data
2.2 NOAA/NWS National Digital Forecast Database
In the 1990s, the NOAA/National Weather Service
(NWS) recognized that it had to evolve its
hydrometeorological products and services beyond text-
based forecasts to meet growing customer/partner
demands. In 2003, the NWS launched the National
Digital Forecast Database (NDFD). The NDFD is an
event driven, information oriented, interactive, and
database.  The NDFD consists of a 7-day forecast for a
set of sensible weather elements on a 5-km domain
which covers the contiguous United States, Alaska,
Guam, Hawaii, and Puerto Rico – see Table 1. Each of
the 122 NWS Weather Forecast Offices (WFO) produces
and maintains the database for its area of responsibility. 
Figure 2 shows examples of NDFD output graphics. 
Using the latest observations, radar and satellite data,
guidance products from the National Centers for
Environmental Prediction (NCEP), and numerical
interactively modify the database using the Gridded
Forecast Editor2.  Several NCEP centers also contribute
forecast information into the NDFD. NWS forecast text,
tabular, and graphic products are generated directly from
the database using product formatters and other output-
defined software.  Also, the database itself is provided as
an NWS product to customers and partners.  This allows
users to access the database for their own applications,
manipulate the database, and extract forecast information
tailored to their specific needs.  In the years ahead, the
NWS will continue to work toward evolving the NDFD
database. Future NDFD expansion will include
information, outlooks, watches, and warnings. 
3. Next-Generation Forecast Workstations
Continuing advances in information technology and
communication capabilities suggest that the rapid
increase in the volume of hydrometeorological data
during the last three decades will continue and may even
accelerate in the years ahead. The proliferation of
automated observing systems and mesonetworks,
coupled with improvements and/or replacements of
existing remote sensing observing systems portend at
least an order of magnitude increase in data.  The next
generation  forecast workstations will need more
bandwidth, storage capacity, and processing power to
handle the expected rapid increase of data. This, coupled
with increased temporal and spatial resolution NWP
model output, will make it imperative that the next
generation forecast workstations are equipped with new,
state-of-the-art visualization and information processing
techniques, including three-dimensional techniques, to
assist forecasters with data analysis and interpretation. 
Sophisticated diagnostic tools will also be required to
examine the data and highlight meteorological processes. 
In addition, the large volume of data will require an
increased reliance on advanced algorithms and
processing techniques to monitor both current and
forecast conditions, extract and portray the most relevant
information, and assist with hydrometeorological
next generation forecast
workstations will assist in the preparation of forecasts,
warnings, and their dissemination through a host of
communication channels. These workstations will also
have the capability to support digital database forecast
Some next generation workstations may also look to
incorporate an Internet-based instant messenger chat
(IMChat) capability to allow NMHSs to communicate
with key customers and partners during significant
hydrometeorological events and all-hazards incidents.
The NWS is currently experimenting with the IMChat
concept in significant hydrometeorological operations.
IMChat allows key customers and partners to get critical
information in real-time for an unfolding time-sensitive
event or incident.  In turn, NMHSs would receive site-
specific reports or other information which can assist
with forecast and warning operations.
3.1 Nowcasting Systems
A number of NMHSs have been developing innovative,
next generation Nowcast systems.  Nowcast systems
range in complexity with some that rack radar echoes
and use extrapolation to produce 0-1 hour nowcasts,
while more complex systems utilize a combination of
NWP output and probabilistic/uncertainty forecast
techniques to extend the Nowcasting time horizon out to
3-6 hours. Some of these systems also incorporate other
remote sensing platforms including satellite and
lightning data.  Many of these systems are still
challenged to optimize the role of the forecaster in the
Nowcast process.  One of the other key focus areas is
incorporating real-time verification and feedback to
forecasters.  An important strength of a Nowcast system
is it’s ability to rapidly generate hydrometeorological
forecast products and disseminate them in a variety of
formats.  This capability will have significant
implications for timely and effective PWS service
delivery.  Several Forecast Demonstration Projects have
been organized through the WMO to test Nowcasting
systems and applications. The first Demonstration
Project was successfully carried out in 2000 at the
Summer Olympic Games in Sydney.  Another
demonstration project is scheduled to be conducted
during the 2008 Summer Olympics in Beijing. 
4. Information Technology Systems and
Since its inception, NMHSs have exploited the Internet
to varying degrees. While almost all NMHSs have an
Internet web page, the dissemination and services
provided vary considerably. The Internet allows NMHSs
to present hydrometeorological forecasts and warnings,
and climate information to its customers, partners, and
the public in graphic and digital formats that would
otherwise be unavailable. It also provides opportunities
to enhance and expand service delivery.  For example,
EC has developed an Internet web site exclusively for the
media that allows them to tailor EC data to their specific
needs.  In another example, the NWS implemented an
aviation-focused initiative called the Collaborative
Convective Forecast Product (CCFP) in partnership with
its aviation community.  Weather-related delays due to
convective activity are the single most disruptive force
within the U.S. National Airspace System.  
The expansion of the Internet in the 1990s, coupled with
new computer and telecommunications technologies, has
led to a proliferation of Information Technology (IT)
systems and applications. The evolution of PWS
dissemination/service delivery integration is directly
linked to the emergence of new computer and
systems (e.g. the Internet, wireless communication
networks). Namely, these innovations allow NMHSs to
provide weather forecasts and warnings in a variety of
new formats (digital, XML, CAP) to meet customer
demands for more precise and accurate environmental
information.  In addition, these new and emerging
technologies offer the opportunity to further integrate
PWS dissemination and service delivery functions. Other
evolving capabilities (PodCasts/VodCasts) can further
enhance PWS service delivery.
4.1 Geographic Information Systems and the Global
Positioning System
Geographic Information Systems (GIS) are designed for
capturing, storing, analyzing and managing data and
associated attributes which are spatially referenced to the
Earth.  The Global Positioning System (GPS), originally
developed in the 1970s by the U.S. for military
applications and transitioned for civilian use in the
1980s, is comprised of 24 earth-orbiting satellites which
provided location specific information as precise as tens
of meters. Together, GIS and GPS provide a powerful
technological tool for NMHSs to enhance their PWS
service delivery.  Utilizing GIS and GPS with mobile
communications networks and devices (cell phones,
PDAs), NMHSs can effectively deliver user and location
specific warnings and forecasts.
The NWS is utilizing GIS technology in its short-fused
hydrometeorological warning program through the
implementation of storm-based warnings (also referred
to as polygon warnings).  Currently, four types of short-
fused warnings (Tornado, Severe Thunderstorm, Flash
Flood, and Special Marine) include polygon information
which takes the form of latitude and longitude pairs
which highlight the threat area. – See Figure 3.  Data
from these warnings are collected and databased into a
real-time set of GIS shapefiles. These files can be
downloaded from the NWS website in real-time and used
by customers and partners in other GIS applications. 
Figure 4 is an example of a graphic display of a NWS
severe thunderstorm warning in northern Florida by
Media Weather Innovations, a private weather provider. 
managers/planners and media partners.  Emergency
managers and the media can quickly access and
download GIS shapefiles via the Internet, add them to
their existing GIS fields, and incorporate them into other
GIS applications.
4.2 EXtensive Markup Language – XML
EXtensible Markup Language (XML) is an Internet-
based language format for documents containing
structured information or data. An Internet markup
language is a mechanism to identify structures in a
document.  The XML specification defines a standard
way to add markup to documents. Structured information
contains both content (words, pictures, etc.) and some
indication of what role that content plays (for example,
content in a section heading has a different meaning from
content in a footnote, which means something different
than content in a figure caption or content in a database
data/information and the document tags are user-defined.
XML is a cross-platform, software and hardware-
independent tool for transmitting data and information. 
It is important to emphasize that XML complements
HyperText Markup Language (HTML) and is not a
replacement for HTML.  XML is designed to describe
data/information while HTML is designed to format and
display data/information.  
Another benefit of XML is its ability to exchange data
between incompatible systems.  In many instances,
computer systems and databases contain data in
incompatible formats. One of the most time-consuming
challenges has been the exchange of data between such
systems over the Internet.  Converting data to XML
format can greatly reduce this complexity and create data
that can be read by a wide array of applications.
4.3 Common Alerting Protocol – CAP
The Common Alerting Protocol (CAP) is an open, non-
proprietary standard data interchange format that can be
used to collect all-hazard warnings and reports locally,
regionally and nationally, for input into a wide range of
information-management and warning dissemination
systems. CAP format uses eXtensible Markup Language
(XML) and standardizes the content of alerts and
notifications across all-hazards including hazardous
material incidents, severe weather, fires, earthquakes,
and tsunamis. CAP’s origins can be traced back to
recommendations of the "Effective Disaster Warnings"
report issued in November, 2000 by the United States
Working Group on Natural Disaster Information
Systems, Subcommittee on Natural Disaster Reduction. 
Systems using CAP have shown that a single
authoritative and secure alert message can quickly launch
captions/scrolls, highway sign messages, and synthesized
voice-over automated telephone calls or radio broadcasts
to effectively alert the public. CAP is a simple but
general format for exchanging all-hazard emergency
hydrometeorological warnings, over a wide variety of
communication networks. CAP allows a consistent
warning message to be disseminated simultaneously over
many different warning systems, thus increasing warning
dissemination task. CAP provides a template for
effective warning messages based on best practices
identified in academic research and real-world
experience. Growing segments of the emergency
management community are embracing CAP as a
comprehensive, all-in-one approach to provide critical
all-hazard information to the public.  In turn, the NWS is
working towards adopting the CAP standard. Figure 5
shows both the raw CAP code and an example of how
CAP is used in real-time from the California office of
Emergency Services.
4.4 Real Simple Syndication – RSS
communication capabilities that can enhance PWS
service delivery.  This includes Real Simple Syndication
(RSS).  RSS is a family of web formats used to publish
frequently updated digital content.  RSS is commonly
used to update news articles and other content that
changes quickly.  Typically, RSS feeds deliver text and
graphic content; however, RSS feeds may also include
audio files (PodCasts) or even video files (VodCasts).  
environmental information.  Rather than the traditional
approach of NMHSs “pushing” hydrometeorological
products to its user community, users install RSS feed
readers which allows them to select and tailor the
environmental information they need to meet their
specific needs.  Users subscribe to a feed by entering the
link of the RSS feed into their RSS feed reader; the RSS
feed reader then checks the subscribed feeds for new
content since on a recurring basis. If new content is
detected, the reader retrieves the new content and
provides it to the user.  Most standard Internet web
browsers (e.g. Firefox, Internet Explorer 7, Mozilla,
Safari) can read RSS feeds automatically.  Alternatively,
users can install a stand-alone RSS feed reader or news
aggregator. Thus, RSS gives the user the ability to
maintain environmental situational awareness and
information from their NMHS as needed.  This approach
also has the added benefit of reducing the load on web
hydrometeorological events and other high-traffic
periods.  Figure 6 shows the United Kingdom Met Office
RSS instruction web page describing how users can
access RSS feeds for their products and the
NOAA/NWS.Internet site with links to available RSS
4.5 Keyhole Markup Language – KML
Keyhole Markup Language (KML) is a recent XML-
based offshoot designed for geospatial data applications. 
More specifically, KML is an XML-based language and
file format for describing three-dimensional geospatial
data and its display in application programs. KML has a
tag-based structure similar to HTML with names and
attributes used for specific display purposes. XML can
be used to store geographic features such as points, lines,
images, polygons, and models for display in Google
Earth and Google Maps.  A KML file is processed by
Google Earth and Google Maps in a similar way that
HTML and XML files are processed by web browsers. 
NMHSs may be able to exploit features of KML to add
another dimension to delivering user and location
specific warnings and forecasts.
5. Future Technology – Dual Polarization Radar
and Phased Array Radar
One of the most exciting, innovative future technology
enhancements for PWS is in the radar remote sensing
arena.  Next generation radar systems (Dual-polarization
Radar, Phased Array Radar) provide the opportunity to
improve severe weather detection, rainfall estimates,
winter weather warning, and increase the lead time for
severe weather hazards including tornadoes and heavy
rain/flash flood events.
Dual-polarization radars transmit radio wave pulses that
have both horizontal and vertical orientations. The
additional information from vertical pulses will greatly
improve forecasts and warning for a variety of hazardous
weather including severe weather, heavy rainfall, and
winter weather events.  Unlike current WSR-88D radars,
which transmit one beam of energy at a time, listen for
the returned energy, then mechanically tilt in elevation
and sample another small section of the atmosphere, a
phased array radar system uses multiple beams, sent out
at one time, so the antennas never need to tilt.  This
results in a complete scan of the entire atmosphere in
about 30 seconds compared to 6 to 7 minutes for the
WSR-88D radar. In addition, the phased array radar
The benefits of phased array radars on PWS are broad
and significant.  They will allow NMHSs to issue more
timely and improved warnings of severe weather hazards
including the potential to issue graphic formatted tornado
warnings up to 45 minutes in advance, improve the lead
time for flash flood warnings and icing forecasts for
aviation interests.
6. Summary
The emergence of new, innovative and technologically
advanced forecast systems and communications systems
provide a host of exciting possibilities for NMHSs to
improve PWS and effectively integrate dissemination
dissemination and service delivery integration will be
dictated in large part by the development and application
of new, innovative computer and telecommunication
technologies and information systems.  Digital database
forecasting offers one of the most fascinating
opportunities to integrate PWS forecast dissemination
and service delivery most effectively to NMHS
customers, partners and the general public.  While it’s
recognized that digital forecasting is in its formative
stages, and new telecommunication technologies are still
emerging, NMHSs should keep abreast of this evolving
forecasting approach.
Next-generation forecast workstations bring the promise
of new methods to assimilate vast amounts of
observational data and NWP output, including new
visualization and information processing techniques, to
assist forecasters with data analysis and interpretation.
These workstations will assist with forecast preparation
and significant event, high-impact hydrometeorological
decision support.  In addition, these workstations will
likely incorporate sophisticated Nowcast systems which
will integrate an array of real-time data and NWP output
to provide prognostic information out 6 hours while also
helping to rapidly generate and disseminate forecast
IT systems and associated applications, including XML,
CAP, and RSS, will allow NHMSs to exploit the latest
telecommunication networks, including broadband,
wireless, and mobile systems, to improve PWS.  Coupled
with GIS and GPS capabilities, NMHSs can satisfy
customer and partner demands forever increasing
precision, accuracy, and detailed, location-specific
hydrometeorological forecasts and warnings. Together,
these efforts will allow NMHSs to cultivate an
innovative and effective PWS program which leverages
technological advances to create a holistic forecast and
warning dissemination, service delivery, and all-hazard
decision support process that best serves the user
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Anonymous h 2012

Created By: Riley Quijano

Department of Earth, Atmospheric, and Planetary Sciences

The Department of Earth, Atmospheric, and Planetary Sciences offers the bachelor's degree in earth, atmospheric, and planetary sciences, and master's and doctoral degrees in earth and planetary sciences, atmospheric sciences, oceanography, and climate physics and chemistry.

Departmental programs apply physics, chemistry, and mathematics to the study of the Earth and planets in order to understand the processes that are active in the Earth's interior, oceans, and atmosphere, as well as the interiors and atmospheres of other planets. The department also uses the basic sciences to understand the past history of the Earth and planets. By combining the past history with models of present physical and chemical processes, faculty and students work to develop an understanding of the dynamics of systems as diverse as the global climate system, regional tectonics and deformation, petroleum and geothermal reservoirs, and the solar system.

Department faculty members teach and carry out research through programs in atmospheres, oceans and climate, geochemistry, geology, geobiology, geophysics, and planetary science. Specific research activities include environmental earth science, global climate change science, planetary missions, and earthquake and exploration geophysics.

Modern problems in these fields are approached by field measurements, laboratory studies, and theory.[1] Experimental facilities for training and research are available not only in departmental laboratories such as the Earth Resources Laboratory, but also in MIT's interdepartmental laboratories such as the Center for Global Change Science, Kavli Institute for Astrophysics and Space Research, Lincoln Laboratory, Haystack Radio Observatory and Millstone Radar facility, and the Wallace Astrophysical and Geophysical Observatories (described in the section on Interdisciplinary Research and Study in Part 3), and in cooperating institutions such as the Woods Hole Oceanographic Institution.

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Undergraduate Study

Bachelor of Science in Earth, Atmospheric, and Planetary Sciences/Course 12
[see degree chart]

The Earth, Atmospheric, and Planetary Sciences Department offers undergraduate preparation for professional careers in a wide range of fields in geoscience (which includes geology, geophysics, and geochemistry), physics of atmospheres and oceans, environmental science, and planetary science and planetary astronomy. Students concentrate in one of these four areas.

The curriculum for the Bachelor of Science in Earth, Atmospheric, and Planetary Sciences ensures a fundamental background through departmental core subjects and advanced study in an area of concentration that includes required subjects and restricted electives. Students are also required to take field and/or laboratory subjects, and to complete an independent research project as part of the degree requirements.

Double Major

Studies in physics, chemistry, biology, applied mathematics, and electrical or civil engineering are directly relevant preparation for work in earth, atmospheric, and planetary sciences. Students from these departments can arrange a program of study in Course 12 leading to a second major in one of the department's areas of concentration.

Five-Year Program

Students with strong academic records from the departments of Earth, Atmospheric, and Planetary Sciences, Chemistry, Physics, Mathematics, Civil and Environmental Engineering, Electrical Engineering and Computer Science, or Chemical Engineering, should be able to complete a Master of Science in Earth and Planetary Sciences, in Atmospheric Sciences, or in Ocean Sciences in one year of additional study, particularly if programs are arranged for this purpose from the beginning of the fourth year.

Applications for graduate enrollment in the department are considered any time after the beginning of the fourth year. Students may receive the Bachelor of Science as soon as the requirements are completed, or may elect to defer the award for simultaneous presentation with the Master of Science.


The requirements for the Minor in Earth, Atmospheric, and Planetary Sciences are as follows:

Core Subjects
Two subjects from:
12.001   Introduction to Geology
12.002   Physics and Chemistry of the Terrestrial Planets
12.003   Physics of the Atmosphere and Ocean
12.006J   Nonlinear Dynamics I: Chaos
12.102   Environmental Earth Science
12.400   The Solar System
One subject from:
18.03/18.034   Differential Equations
5.60   Thermodynamics and Kinetics

Restricted Electives
Two or more additional Course 12 subjects within one of the EAPS concentration areas, approved by the minor advisor; and 12 units from the following:
Lab: 12.115, 12.119, 12.307, 12.410J
Field and IAP: 12.120, 12.141, 12.213, 12.214, 12.221, 12.310, 12.411
Independent Study: 12.IND, 12.UR

The Earth, Atmospheric, and Planetary Sciences Department jointly offers a Minor in Astronomy with the Department of Physics (Course 8). A detailed description and list of requirements for this minor is available in the Interdisciplinary Undergraduate Programs and Minors section in Part 3.


Additional information may be obtained from the department's Education Office, Room 54-912, 617-253-3381 begin_of_the_skype_highlighting FREE 617-253-3381 end_of_the_skype_highlighting.

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Graduate Study

The Department of Earth, Atmospheric, and Planetary Sciences offers opportunities for graduate study and research in a wide range of fields, as indicated by the detailed subject descriptions in the online MIT Subject Listing & Schedule, http://student.mit.edu/catalog/index.cgi. This coursework is the usual prelude to a thesis demonstrating that the student is capable of independent and creative research. A successful thesis leads to a graduate degree: a Master of Science, a Doctor of Philosophy, or a Doctor of Science in the field of specialization.

A graduate thesis may have either a theoretical, experimental, or observational focus. Modern laboratory facilities, computers, instrumentation, and extensive collections of specimens and data are available to students. Field study is an essential part of the graduate curriculum in geology, geophysics, and geochemistry, and special arrangements may be made for summer employment and field research on departmental projects and with industrial organizations and government agencies. In oceanography, sea-going observational research is an important part of the educational experience. In atmospheric science, climate studies, and oceanography, graduate study includes a mixture of theoretical and experimental studies sharing a common appreciation of the dynamics of the underlying processes.

Entrance Requirements for Graduate Study

In addition to the general institute requirements for admission listed in the section on Graduate Education in Part 1, the department requires preparation equivalent to the curriculum for the Bachelor of Science in Earth, Atmospheric, and Planetary Sciences at MIT for graduate studies in that field. For atmospheric sciences, climate studies, meteorology, and oceanography, the most essential element is a sound preparation in mathematics and physics, supplemented if possible by some chemistry. Students taking their undergraduate work at other institutions are advised to include in their programs the equivalent of the mathematics and physics contained in the MIT undergraduate curricula. If students are not fully prepared in certain of the fields or required subjects, they usually are asked to extend their studies in these areas while pursuing advanced work. The doctoral program can be entered without a Master of Science as a prerequisite.

Joint Program with the Woods Hole Oceanographic Institution

MIT and WHOI have established a program in oceanography that leads to a jointly awarded degree of Master of Science, Doctor of Philosophy, or Doctor of Science. For more information, see the program description at the end of Part 3.

Master of Science in Earth and Planetary Sciences, in Atmospheric Science, or in Climate Physics and Chemistry

The General Degree Requirements for the degree of Master of Science in Earth and Planetary Science, in Atmospheric Science, or in Climate Physics and Chemistry are described under Graduate Education in Part 1. An individual program of study and research is arranged to suit the special background, needs, and goals of each student. The program is worked out in detail by the student with his or her personal faculty advisor and a departmental committee. There are no foreign language requirements for the degree. Master's students in climate and atmospheric science have access to the facilities of the joint MIT-WHOI program.

Doctor of Philosophy and Doctor of Science

General Degree Requirements for the degree of Doctor of Philosophy or Doctor of Science are given in the section on Graduate Education in Part 1. The department does not require candidates for the doctorate to present evidence of competence in a foreign language, but it strongly urges that candidates for the doctorate acquire intermediate competence in one or more languages. A specialized program of study and research is tailored to each student's background, needs, and goals by the student in consultation with a faculty advisor and a departmental committee. A doctoral candidate's program should be broad and include formal study in other departments in addition to the specialized subjects that prepare the candidate for thesis research. Thesis research normally begins immediately after successful completion of the general examination by the end of the second year. The general examination is intended to test the candidate's aptitude and preparation for independent research.

Thesis research is closely supervised by one or more faculty members interested in and knowledgeable about the research topic, who are chosen by the student and may be members of other departments. The thesis is expected to meet high professional standards, and to be a significant original contribution to the scientific field.

Teaching and Research Assistantships

The department offers a considerable number of research and teaching assistantships each year. Research assistants work on one of the many research projects in the department, often related to the student's thesis research. Teaching assistants assist in laboratory instruction or in the preparation of teaching materials and the grading of papers.

The department also offers several fellowships beyond normal teaching and research assistantships. Selection of individuals is based on the excellence of the applicant's record.


Additional information regarding academic and current research programs in the department, admission requirements, assistantship appointments, and financial aid may be obtained by writing to the department's Education Office, Room 54-912, 617-253-3381 begin_of_the_skype_highlighting FREE 617-253-3381 end_of_the_skype_highlighting.

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Research Laboratories and Programs

Earth Resources Laboratory

The Earth Resources Laboratory (ERL) is one of the premier research laboratories in the world in the areas of applied geophysics and quantitative geology. The lab studies the spatial heterogeneity of the earth's upper crust through geophysical imaging, geological process modeling, and the interactions between rock pore systems and migrating fluids. Laboratory activities are centered around theoretical, experimental, and observational research programs in basic science that have both industrial and academic applications. Research at the lab is supported by industry and government agencies.

ERL's major research activities include: elastic wave propagation in complex media; characterization of reservoir properties such as fracture density, in-situ stress, and fluid mobility from seismic and well log data; turbidite depositional dynamics; field mapping of reservoir scale geologic analogs in Western Africa; electroseismic phenomena; imaging and simulation of pore-scale fluid flow; borehole acoustics; reservoir imaging from surface and borehole seismic data; GPS measurements of crustal deformation in the Eastern Mediterranean, including the North Anatolian fault system in Turkey; and geophysical monitoring of groundwater contaminant movement.

ERL's computation environment consists of a large network of workstations and personal computers, as well as the Reservoir Science Visualization Laboratory, which includes a number of high performance workstations running data analysis and visualization software. This facility is used to enhance and expand ERL's research activities in petroleum reservoir imaging and monitoring, environmental geophysics, and geologic mapping and remote sensing. ERL also has a wide range of experimental facilities and equipment, including a large-scale (5m by 5m) sediment dynamics tank, and Ultrasonic Laboratory for seismic imaging and borehole experiments, and field equipment for seismic, electrical, and GPR surveys.

Further information can be obtained through ERL headquarters, Room 54-1814, or by calling Professor Robert van der Hilst at 617-253-6977 begin_of_the_skype_highlighting FREE 617-253-6977 end_of_the_skype_highlighting.

Center for Global Change Science

The Center for Global Change Science (CGCS) seeks to address long-standing scientific problems that impede our ability to accurately predict changes in the global environment. Established in 1990, CGCS is an interdepartmental organization that conducts research on global climate processes, climate observations, and past climate variations. Participants include faculty, staff, and students from a variety of natural science and engineering disciplines. The center's activities also involve substantial multidisciplinary cooperative efforts focused on climate modeling, through the Climate Modeling Initiative (http://paoc.mit.edu/cmi/), and climate-policy research, through the Joint Program on the Science and Policy of Global Change (http://mit.edu/globalchange/).

For further information, see the center description in the section Interdisciplinary Research and Study in Part 3.

Joint Program on the Science and Policy of Global Change

The Joint Program on the Science and Policy of Global Change conducts independent analyses of climate-policy issues and research on climate science. It is a cooperative effort of the Center for Global Change Science and the Center for Energy and Environmental Policy Research that brings together natural and social scientists to address global environmental change and human-climate interaction. The program is a highly visible and well-funded effort, providing rigorous integrated assessment of the climate change issue to governments, industry, and the public. The cornerstone of the program's research is an interacting set of models of the world economy (human activities) and the earth system (coupled ocean, atmosphere, land, and ecosystems). The program cooperates closely with the Ecosystems Center of the Marine Biological Laboratory in Woods Hole, MA; the MIT Climate Modeling Initiative; and other MIT environmental programs.

For further information, see the program description in the section Interdisciplinary Research and Study in Part 3.

George R. Wallace, Jr. Astrophysical Observatory

The George R. Wallace, Jr., Astrophysical Observatory is a versatile facility for research and teaching optical astronomy. The observatory located in Westford, MA, has two optical telescopes with 16-inch and 24-inch diameters and unique electronic instrumentation. The telescopes are used in formal instruction for student research projects, and as testbeds for instrumentation to be used with larger telescopes. Further information on the Wallace Observatory may be obtained by contacting Professor James L. Elliot, Room 54-422, 617-253-6308 begin_of_the_skype_highlighting FREE 617-253-6308 end_of_the_skype_highlighting, jle@mit.edu, or visit http://web.mit.edu/wallace/.

Wallace Geophysical Observatory

The George R. Wallace, Jr., Geophysical Observatory is a unique research facility designed to monitor ground motions and to aid in the development and testing of new seismic and other geophysical instrumentation. It is also a key component of MIT's five-station seismic network in New England.

Located 35 miles north of Boston in Westford, MA, the observatory has a large, multi-room underground vault and a surface control room. The vault has a controlled temperature environment and instrument piers resting directly on the basement granite. The observatory contains sensitive seismometers and instruments for monitoring ground tilts and the earth's tidal motions. The surface building houses a work area and control and recording instruments. Data from the observatory are telemetered directly to the Earth Resources Laboratory of the Department of Earth, Atmospheric, and Planetary Sciences. The data from the observatory and the New England Seismic Network are recorded, displayed, and analyzed by three dedicated COMPAQ computers, which are also connected to workstations to facilitate data sharing and transfers. Data from the observatory along with the numerous resources of the department provide a unique facility for undergraduates, graduate students, and staff to pursue research concerning the interior of the earth.

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Anonymous g, 2012

Created By: Riley Quijano

At the University of Hawai‘i at Manoa

Thank you for your interest in our department. We are always seeking to recruit excellent students for both our undergraduate and graduate programs. Meteorology has been an academic discipline at University of Hawai‘i at Manoa for over 50 years. The department has built an enviable national and international reputation for research and education, offering both undergraduate (B.S.) and graduate (M.S. and Ph.D.) degree programs. Since 1965 the University has been a member of the University Corporation for Atmospheric Research.


Image placeholder for slideshow. The department is part of one of the world’s most active schools in the geosciences: the University of Hawai‘i School of Ocean and Earth Science and Technology (SOEST). SOEST has about 200 faculty members who study a wide variety of phenomena related to the physics, chemistry and biology of the solid earth, the ocean, and the atmosphere. Meteorology faculty and student offices are located in the Hawai‘i Institute of Geophysics (HIG) building and the adjacent Pacific Ocean Sciences and Technology (POST) building.

Research: In the Laboratory…

Research has been central to the department’s activities since its inception. Despite the department’s modest size, an impressive array of research projects are being pursued. Projects involving experimental work as well as computer modeling and theoretical calculations are being undertaken by our faculty and students. Our students now have thesis topics that involve study of a variety of atmospheric phenomena on a wide range of space and time scales. However, our unique situation as the only world-class university located in the middle of the Pacific Ocean has kept our main focus on issues relating to the weather and climate of the tropical Pacific and the Asian-Pacific regions.

…and in the Field

Department faculty have participated in a series of field experiments on the island of Hawai‘i and elsewhere. These experiments have generally emphasized investigations of cloud physics, and more recently, of convective and mesoscale phenomena. We helped organize and conduct the Hawaiian Rainband Project (HaRP) in 1990. Faculty and students also have participated in the Experiment on Rapidly Intensifying Cyclones in the Atlantic (ERICA) in 1989, the Convection and Precipitation/Electrification Experiment (CaPE) in 1991, the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean Atmosphere Response Experiment (COARE) in 1993, the Aerosol Characterization Experiment (ACE) in 1995, and Atmospheric Investigation, Regional Modeling, Analysis and Prediction (AIR–MAP) in 2004. Many graduate students find thesis topics in the analysis of results of such specialized field campaigns, or in related modeling activities.

Photo of undergrads at NWS office.

Undergraduate meteorology students visiting the National Weather Service (NWS) Honolulu Forecast Office at UH looked over the shoulder of lead forecaster Pete Donaldson as he studied the monitor. The NWS Honolulu Forecast Office moved to the UH-Manoa campus from the airport in 1995. The Honolulu office is one of only 13 nationally that is located on a university campus and in our case it actually shares the HIG building with the Meteorology Department.

Forecasting and Practical Applications

We are fortunate that the National Weather Service Honolulu Forecast Office is located in the HIG building, providing access to real time weather data and allowing interactions with the operational forecasters. Several of our students have actually worked part-time at the forecast office. Some of the department’s research activities are directly related to improving short-term weather forecasts for the Hawaiian Islands, including specialized forecasts for the use of astronomers operating the world renowned observatories on Mauna Kea on the island of Hawai‘i.

Support for practical application of weather and climate information in Hawai‘i is provided by the Hawai‘i State Climate Office, which is directed by Prof. Pao-Shin Chu in our department. We also provide important practical support for the local office of the U.S. Forest Service.

Longer Timescales and Climate Studies

Studies of the basic physics of tropical atmospheric circulations on seasonal and longer timescales, notably the El Niño phenomenon and the Asian monsoon circulations, have a long and distinguished history in the department and in our sister Oceanography department. In 1997, our endeavors in climate studies were significantly enhanced by the advent of the International Pacific Research Center (IPRC), now located in the POST building. The IPRC is a joint Japan-US research center for the study of climate variations and long-term climate change in the Asian-Pacific region. Several Meteorology department faculty members also have appointments in the IPRC.


[1] Modeling and data analysis in the department is facilitated by a network of desktop workstations and personal computers. Individual faculty have access to powerful computing resources through their own facilities or collaborations with other institutions.

With funds from the Unidata Equipment Award Program and a generous cost match from SOEST, the department has recently undertaken an upgrade of its VisionLab instructional computer facility. The workstations in the VisionLab are also used for research.

[2] For field work the department has recently acquired a new InterMet 3000 portable radiosonde system. This provides balloon-borne measurements of temperature, pressure, water vapor, and GPS-determined position (from which winds can be derived).

More information for students

You can download our brochures (as PDFs) presenting details of our undergraduate and graduate programs here, or follow the links to lists of our faculty and courses, descriptions of undergraduate and graduate degree programs, and information on how to apply for graduate studies.

The Weather Server

The Department also maintains a Weather Server page displaying real time weather observations and forecasts for Hawai‘i, the central Pacific region and the US Mainland.

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Anonymous f, 2012

Created By: Riley Quijano

Meteorology & Physical Oceanography

About MPO

The Division of Meteorology and Physical Oceanography (MPO) of the Rosenstiel School of Marine and Atmospheric Science (RSMAS) is engaged in research and graduate instruction in the physical processes governing the motion and composition of the ocean and atmosphere. The program ranges from direct observation to theoretical and numerical modeling of the earth-atmosphere system. There are currently 35 students enrolled in the program. Students come from a variety of educational backgrounds (marine science, meteorology, physics, mathematics, engineering, etc.)


[1]A modern fleet of research vessels, small boats, excellent computer facilities, a highly technical field capability, and an extensive library provide the perfect research environment for both budding and accomplished meteorologists or physical oceanographers. Combined with the other on-campus divisions and unique tools like the Center for Southeastern Tropical Advanced Remote Sensing, the School offers opportunities in meteorology and physical oceanography available at few other institutions.


Applicants must take the GRE, and those whose first language is not English must pass the Test of English as a Foreign Language (TOEFL) with a score of at least 550.A strong background in physics and mathematics is recommended.

Funding Opportunities

The overwhelming majority of MPO students are supported as research assistants. These assistantships, which are awarded competitively, provide a monthly stipend and cover tuition costs. Students not supported as research assistants are generally supported on special fellowships provided by their employer or, for some non-U.S. students, their home country.

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Anonymous b, 2012

Created By: Riley Quijano
[1]Part Time (1 - 11 credit hours)
Tuition (per credit in excess of 20)*
Audit - no degree credit (per course)
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Annual (Cover both Fall &
Spring/Summer sessions)
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Revised 2/27/2012
Full Time (12 - 20 credit hours)
Tuition (Flat Rate)
Tuition per credit
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Center Fee
2012 - 2013 Semester Tuition and Fees Rates Undergraduate*
** Intensive English Program (IEP) 14 week sessions and less than 6 credits.
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a. The Activity fee is optional in the summer if Part time.
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Michael Mishchenko, August 10, 2012

Created By: Riley Quijano
Suomi satellite brings to light a unique frontier of
nighttime environmental sensing capabilities
Steven D. Miller
, Stephen P. Mills
, Christopher D. Elvidge
, Daniel T. Lindsey
, Thomas F. Lee
and Jeffrey D. Hawkins
Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO 80523;
Northrop Grumman Aerospace Systems, Redondo
Beach, CA 90278;
National Geophysical Data Center, National Oceanic and Atmospheric Administration, Boulder, CO 80305;
Regional and Mesoscale
Meteorology Branch, Center for Satellite Applications and Research, National Environmental Satellite, Data, and Information Service, National Oceanic
and Atmospheric Administration, Fort Collins, CO 80523; and
Satellite Meteorological Applications Section, Marine Meteorology Division, Naval Research
Laboratory, Monterey, CA 93943
Edited by Michael Mishchenko, National Aeronautics and Space Administration Goddard Institute, New York, NY, and accepted by the Editorial Board
August 10, 2012 (received for review April 25, 2012)
[1]Most environmental satellite radiometers use solar reflectance
information when it is available during the day but must resort at
night to emission signals from infrared bands, which offer poor
sensitivity to low-level clouds and surface features. A few sensors
can take advantage of moonlight, but the inconsistent availability
of the lunar source limits measurement utility. [2]
Here we show that
the Day/Night Band (DNB) low-light visible sensor on the recently
launched Suomi National Polar-orbiting Partnership (NPP) satellite
has the unique ability to image cloud and surface features by way of
reflected airglow, starlight, and zodiacal light illumination. [3]Examples
collected during new moon reveal not only meteorological and
surface features, but also the direct emission of airglow structures in
the mesosphere, including expansive regions of diffuse glow and
wave patterns forced by tropospheric convection. The ability to
leverage diffuse illumination sources for nocturnal environmental
sensing applications extends the advantages of visible-light information to moonless nights
airglow/nightglow | nocturnal remote sensingThe sky on a dark, moonless night is, in fact, immersed withina sea of visible-spectrum light that the dark-adjusted human eyecan only begin to discern. The primary sources are the polar aurora,airglow, integrated starlight (including the Milky Way), andzodiacal light (1–3). Auroras, although a relatively strong source,are ephemeral and confined to high latitudes. The other sourcesproduce a complex global distribution of nighttime diffuse skybrightness that varies considerably across space, time, and spectrum. At visible and near infrared wavelengths (e.g., 0.4–1.1 μm),the combined illumination from these sources yields down-wellingradiances at Earth’s surface in the range ∼10−11to 10−9W·cm−2·sr−1·μm−1(3), or approximately 1 billion times fainter than sunlight.Low-light imaging capabilities have existed on the OperationalLinescan System (OLS) on the Defense Meteorological SatelliteProgram (DMSP) constellation since the late 1960s. The OLS wasdesigned to amplify visible light and detect clouds under twilight andmoonlight (e.g., signals down to ∼10−8W·cm−2·sr−1·μm−1) illumination conditions (4) but soon revealed many additional capabilitiesbased on signals from both natural and anthropogenic sources (5–8).The Suomi National Polar-orbiting Partnership (NPP) satellite(http://npp.gsfc.nasa.gov) was launched on October 28, 2011, andplaced into an 834-km altitude sun-synchronous orbit with localequatorial crossing times of ∼1:30 PM and 1:30 AM. Named inhonor of Verner E. Suomi, considered widely as the “father ofsatellite meteorology,” NPP provides risk reduction for the JointPolar Satellite System (JPSS) series of National Oceanic andAtmospheric Administration (NOAA) operational meteorological satellites and continuity to the National Aeronautics andSpace Administration (NASA) Earth Observing System (EOS)Terra and Aqua climate research satellites (9).Suomi NPP carries the Visible/Infrared Imager/RadiometerSuite (VIIRS), an optical spectrum (22 bands spanning ∼0.4–13μm) sensor providing imagery at high spatial resolution (0.375–1.6 km, band dependent) across a 3,000-km-wide swath. Includedon VIIRS is a next-generation low-light sensor, the Day/NightBand (DNB). The DNB has a measured spectral response of505–890 nm (full width at half maximum, with nominal bandcenter wavelength of 705 nm) and features several advances tothe heritage OLS, including full calibration and improved spatial(0.74 km vs. ∼3 km) and radiometric (14-bit vs. 6-bit) resolutions(10). Three stages of gain allow the DNB to span the dynamicrange of radiances encountered during the daytime, twilight, andnighttime with measured radiometric uncertainties of 3.5%,7.8%, and 11.0%, respectively. The data are calibrated andspectrally normalized with respect to an on-board solar diffuser,which has a reflectance that is monitored for stability. Noiseequivalent radiance increases from ∼1 × 10−10W·cm−2·sr−1atnadir to ∼3 × 10−10W·cm−2·sr−1at scan edge.The current findings came about unexpectedly during routineinstrument check-out procedures for the VIIRS/DNB. To characterize and remove sensor noise and offset patterns, we examined astronomically dark scenes over the open oceans duringnights around the new moon (i.e., completely devoid of sunlight,moonlight, and anthropogenic light contamination). Upon firstinspection of these data, the noise pattern was found to containirregularly distributed structures. The anomalous structures werediscovered to be meteorological clouds (Fig. 1) illuminated by anunanticipated source of visible light.Sources of Night Sky Brightness and Relative MagnitudesA complete description of the nonlunar nighttime illuminationsources can be found in the reviews of refs. 1 and 3. We shall limitour discussion here to the globally ubiquitous sources (namelyairglow, starlight, and zodiacal light), referring to these collectively as “diffuse illumination, multisource” (or “DIM”) emissionsof nighttime visible light.The zodiacal light (11) arises from sunlight scattered by interplanetary dust in the solar system. Because this dust is concentrated along the ecliptic and increases in density with proximity tothe Sun, there is a strong spatial structure to this source (ref. 3,figure 37). At high elongation angles from the Sun (i.e., near localmidnight, approximately the time of the Suomi NPP overpass), thisAuthor contributions: S.D.M. designed research; S.D.M. performed research; S.D.M.,S.P.M., and C.D.E. contributed new reagents/analytic tools; S.D.M., S.P.M., C.D.E., D.T.L.,T.F.L., and J.D.H. analyzed data; and S.D.M., S.P.M., and T.F.L. wrote the paper.The authors declare no conflict of interest.This article is a PNAS Direct Submission. M.M. is a guest editor invited by theEditorial Board.Freely available online through the PNAS open access option.1To whom correspondence should be addressed. E-mail: steven.miller@colostate.edu.This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1207034109/-/DCSupplemental.15706–15711 | PNAS | September 25, 2012 | vol. 109 | no. 39 www.pnas.org/cgi/doi/10.1073/pnas.1207034109light source is minimized, with an expected 640-nm radiance rangespanning roughly 0.4–1.1 × 10−10W·cm−2·sr−1·μm−1(from eclipticpoles to equator, respectively).Starlight is composed mainly of contributions from the ∼8,500visible stars and the integrated light from the ∼1011subvisible starsof the Milky Way. The brightness of the galactic source is highlyvariable (12), with the largest values along the galactic equator andsignificantly smaller values at the poles (ref. 3, table 36). Consequently the magnitude of this source varies over the course of theyear, smallest in December and peaking in July. The combinedstarlight source produces 640-nm radiances in the range of roughly1.8–4.0 × 10−10W·cm−2·sr−1·μm−1. Contributions from the diffusescatter of galactic and cosmic light by interstellar dust are twoorders of magnitude lower and considered here to be negligible.Among the DIM sources, airglow dominates in terms of itsmagnitude, dynamic range, and space/time variability, and soreceives special attention here. Airglow refers to the self-illumination of the upper atmosphere via chemiluminescence processes.Nocturnal airglow (called “night glow”) results from the photoionization of atmospheric gases by ultraviolet (UV) sunlight. Nightglow brightness ranges from 10−10to 10−9W·cm−2·sr−1·μm−1(13)within the DNB sensor response when viewed from the surface andat local zenith. Whereas the OLS has not demonstrated the abilityto produce useful meteorological imagery from the DIM sources,the slight red shift of the DNB sensor response (toward the significant near-infrared Meinel OH* airglow bands; see Fig. S1)makes it inherently more sensitive to these emissions.At the surface, the airglow layer appears brightest (a factor of∼4 larger than the zenith value) at an elevation angle of approximately 10° (the van Rhijn function, e.g., ref. 14). Airglow asseen from space has been documented from the Space Shuttle(15) and more recently from the International Space Station(ISS; http://eol.jsc.nasa.gov/Videos/CrewEarthObservationsVideos).Fig. 2, taken by astronauts on board the ISS, shows the relativebrightness and distribution of several nocturnal light sourcesincluding the airglow layer.Airglow Spectral/Space/Time CharacteristicsAirglow emissions occur both as distinct bands and as continuumemission, spanning the UV through the visible and into the nearinfrared (16, 17). Significant contributions with respect to theDNB response include atomic oxygen at 557.7, 630, and 636 nm(altitudes between ∼250–300 km), atomic sodium at 589.0 and589.6 nm, excited hydroxyl (OH*) radicals (500 nm out to 4.5μm), and molecular oxygen from 761.9 nm (A-band) and 864.5nm. The dominant OH* emission layer is geometrically thin (10–20 km), occurring around a critical air density at approximately85 km where excited species are abundant and the favorablemechanism for energy dissipation is photon emission.Airglow emissions are highly variable spatially, seasonally, anddiurnally (18–20) and track changes in solar insolation, atmospheric density, and atomic oxygen availability. This behaviorincludes a semiannual oscillation in maxima with amplitudevariations that are lower in the tropics and higher at midlatitudes(20–22). Regionally, the emissions produce complex transientbanding or patch-like structures associated with planetary waves(23) and mesospheric tides (24, 25). At finer spatial scales,emission features are associated with ionospheric disturbancesforced by atmospheric gravity waves (26, 27). The observedstructures have been tied to tropospheric convection and seismicactivity, with the latter proposed as a means for early detectionof tsunamis (28).Previous MeasurementsThe Orbiting Geophysical Observatory (OGO-4) provided the firstglobal maps of the time-varying airglow distribution and intensity(19). More recent airglow monitoring sensors include the WindImaging Interferometer (WINDII; ref. 24), the Special Sensor UVSpectrographic Imager (SSUSI; ref. 29), the Optical SpectrographIR imager (OSIRIS) limb-viewing camera (30), and the Thermosphere Ionosphere Mesosphere Energetics and Dynamics(TIMED) instrument (25). These sensors were designed to characterize upper atmospheric properties that influence high frequencycommunications and near-field sources of light contamination thatimpact astronomy, as opposed to meteorological applications.Early photometer observations from OGO-4 suggested a possible meteorological utility of airglow (31), although the nonimaging and spatially coarse (∼100 km) nature of thosemeasurements permitted only crude inference of transitionsbetween low and high albedo features (e.g., crossing from oceanto desert). Similarly, the DMSP/SSUSI NPS (a nonimagingphotometer) enlists a secondary measurement at 629.4 nm to330N0N0 030S 30S1120E 20E1150E 50E1180801150W 50W1120W 20W990W0W120E150E180150W120W90WFig. 1. Low-light imagery from a series of adjacent Suomi NPP VIIRS/DNB nighttime passes over the Pacific Ocean on the night of February 22, 2012. Thecoverage domain spans 20,000 km east-to-west and 12,500 km north-to-south, with geopolitical boundaries drawn in green. The data were collected duringnew moon conditions (no sunlight or moonlight present). In addition to city light emissions (e.g., L), the observations capture clouds (e.g., C) illuminated byreflected airglow, starlight, and zodiacal light. Also apparent are broad, diffuse regions of primary airglow emission (e.g., A).Miller et al. PNAS | September 25, 2012 | vol. 109 | no. 39 | 15707ENVIRONMENTALSCIENCEScharacterize and remove background contributions from Earth’salbedo. To date, the only documented use of nonsolar/lunarsources for cloud imaging comes from surface-based camerasystems (32), based on cloud extinction of down-welling airglowemissions as opposed to cloud reflectance.Example ImageryFig. 1 shows VIIRS/DNB cloud imagery over the Pacific Oceanfrom several consecutive nighttime passes in conditions completely devoid of both sunlight and moonlight. To avoid edge-ofscan noise effects, the data were cropped at a maximum sensorzenith angle of 60°, resulting in small coverage gaps betweenadjacent passes at lower latitudes. City lights appear as discrete,bright features. Additional examples are published (Figs. S2–S4).To compare the relative brightness of various illuminationsources, we produced normalized distributions of DNB radiance(in W·cm−2·sr−1) from the north/central Pacific Ocean duringnighttime new moon (i.e., only DIM sources), nighttime full moon,and daytime overpasses. Fig. 3 shows that nighttime scenes illuminated by full moon are roughly 1 million times fainter than thedaytime, and the new moon scenes are approximately 100 timesfainter than full moon. Secondary modes in the full moon anddaytime distributions correspond to lunar and solar glint (specularreflection off the ocean surface) regions, respectively.Nighttime detection of low clouds and other near-surface features in the thermal infrared is problematic because of poorthermal contrast. Here, DIM light imagery offers distinct advantages. Fig. 4 compares VIIRS DNB and M15 (10.7 μm) observations of a low cloud layer over the northern Korean Peninsula. Thewestern and northern edges of the low cloud field are difficult todiscern over land in the infrared imagery but stand out readily inthe DIM light imagery. The imagery also reveals details of the lowcloud structure below optically thin cirrus.Fig. 5 shows a DIM light image of a convective system over thePacific Ocean. The lightning flash (which appears as a brightsegment oriented along a DNB scan line, due to the scanningnature of the sensor) and convective clouds are features thatcould have been detected with heritage DMSP/OLS sensor.However, in addition to these features, the DNB reveals a trainof mesospheric gravity waves in the primary airglow emission,originating from the area of convection and propagating away tothe east/northeast.Source Determination and AnalysisWe considered the possibility that thermal emission might explainthe cloud detections. Ground tests of the silicon-based DNBdetectors showed no sensitivity to wavelengths > 0.91 μm, andeven at this limit the levels of blackbody emission are vanishinglysmall—at least 10 orders of magnitude below minimum detectionlimits. Before the thermal infrared VIIRS bands are cooled to their80 K operational temperature, any cross talk with the DNB wouldhave manifested as white noise as opposed to the coherent structures observed, and the character of DNB imagery did not changeas these bands were cooled. Further evidence against a thermalAirglowMoonAuroraStarlightCity LightsISSSolar PanelsFig. 2. Earth’s limb as seen from the International Space Station on February 1, 2012, 06:11:39 UTC, over the northern Atlantic Ocean. The view is to thenortheast, and shows qualitatively the relative brightness and distribution of various sources of nighttime illumination including airglow, the aurora borealis,the gibbous moon, starlight, and city lights. The lunar source is significantly brighter than the DIM sources, appearing like a star in this exposure. A solar panelfrom the ISS appears in the foreground. (Nikon D3s image ISS030-E-73400 courtesy of the Image Science and Analysis Laboratory, NASA Johnson Space Center).Fig. 3. Distributions of Suomi NPP VIIRS DNB-measured radiances over thenorth/central Pacific Ocean for nighttime new moon, full moon, and daytimescenes. The secondary low-radiance modes (G) of the full moon and daytimedistributions are due to moon and sun glint (respectively) off the oceansurface—a characteristic not seen in the extended diffuse light sources.15708 | www.pnas.org/cgi/doi/10.1073/pnas.1207034109 Miller et al.leak came from the simple observation that clouds in the tropicsappear brighter than the surrounding clear-sky ocean background.This behavior is opposite to the emissive signature expected fromcool clouds observed against a warmer underlying surface butconsistent with visible light reflectance of clouds observed againsta low albedo ocean background.The imagery in Figs. 1, 4 and 5 appear similar to daytime observations, which reveals synoptic-scale patterns of migratory stormclouds, maritime boundary layer clouds, and tropical convection.One notable difference from daytime imagery, however, is thepresence of broad (∼1,000 km scale) regions of diffuse brightness.These features, as noted in Fig. 1, are thought to be areas whereprimary airglow emissions are locally strong enough for the DNB todetect directly. Similar structures were observed on all nights but indifferent locations. Their scale and distribution are consistent withOGO-4 airglow observations (19).Other characteristics of the DNB imagery speak to the uniquenature of the DIM illumination. Note in Fig. 3 the smooth lowend tail structure that is unique to the new moon distribution.The secondary low-radiance modes seen in the daytime and fullmoon cases come primarily from the solar and lunar glintregions. The lack of such a glint mode in the new moon distribution is consistent with the extended diffuse nature of the DIMemissions. The pan-horizon illumination from airglow representsa fundamental difference from the highly directional solar/lunarsources in the sense that cloud shadows will be minimized—potentially improving cloud masks.Concerning the airglow waves observed in Fig. 5, the measuredhorizontal wavelength of ∼33 km is consistent with thunderstorm-induced waves observed by the Midcourse Space Experiment (MSX) midwave-infrared (4.3 μm) limb sounder data (33,34). Sensitivity to both primary and reflected DIM light sourcesprovides a unique perspective on coupling between the troposphere and mesosphere. Additional examples of these wavescompared against thermal infrared imagery are published (Figs.S5–S7). In all cases, the waves were not present in correspondingVIIRS thermal infrared imagery.Research and Operational ImplicationsThe information content of most measurements from meteorological satellites falls off markedly at night, particularly with regardto lower tropospheric clouds (owing to poor thermal contrast),which play a key role in defining Earth’s energy budget (35).Sensing based on DIM light sources could improve the nocturnallow cloud climatology. In turn, it could improve the fidelity of thesea surface temperature (SST) climate data record that is fundamental to our assessments of climate change, because SSTs arederived from nighttime observations and require a cloud screeningthat is inherently problematic for low clouds (36). As shown in Fig.4, the DIM light measurements hold potential to improve nocturnal low cloud masks and, thereby, improve the uncertaintystatistics associated with this key climate parameter.Low clouds and fog also pose significant hazards to transportation by air, land, and sea. At high latitudes, detecting cloudsover cold land surfaces and identifying snow and sea iceboundaries are particularly challenging tasks, especially duringthe winter months when sunlight is unavailable for extendedperiods. Although multispectral techniques (37–39) in manycases overcome thermal contrast issues in nocturnal low clouddetection, these algorithms face insurmountable difficulties inLow Clouds LLow Clouds ow Clouds35N 35N440N0N1125E 25E 125E1130E 30E 130EA BLow Clouds LLow Clouds ow Clouds35N 35N440N0N1125E 25E 125E1130E 30E 130ETThin hinCCirrus irrusThinCirrusFig. 4. VIIRS/DNB low-light imagery (A) of the Korean Peninsula on the night of February 23, 2012, at 1730 UTC during new moon, showing low clouds on theeastern coast and superior edge contrast over land compared with VIIRS/M15 (10.763 μm) thermal infrared imagery (B). Note in particular the western andnorthern edges of the cloud formation.115N5N110N0N55NN1150W 50W1140W 40W1145W 45WLLightning ightningFFlash lash15N10N5N1155WW 155W150W145W140WLightningFlashFig. 5. DNB imagery of thunderstorms (lightning flash indicated) in thetropical central Pacific Ocean on February 22, 2012, at 1107 UTC (a zoomedin subset of Fig. 2). Airglow waves are evident in the vicinity of the storms.The waves, which have wavelength λ ∼ 33 km, appear to propagate radiallyoutward from the area of convection and extend far beyond the anvil cirrus.Miller et al. PNAS | September 25, 2012 | vol. 109 | no. 39 | 15709ENVIRONMENTALSCIENCESthe presence of overriding cirrus. DIM light imagery, with itsability to peer through optically thin cirrus layers, holds uniquevalue for overcoming this problem.Although the VIIRS/DNB has demonstrated the potential ofDIM light, future sensors could be optimized to better exploitthese signals. For example, geostationary-based sensors couldprovide the first continuous (24-h) visible light observing capability. Such time-resolved imagery would allow for monitoringprimary airglow emissions, including mesospheric wave detection(Fig. 5) in support of tsunami warning systems. Low earthorbiting satellites such as Suomi NPP must conduct short integration times per sample because of their motion relative tothe surface, but with geostationary satellites, the observed sceneis essentially fixed, allowing for much longer integration times.This staring capability would help to overcome the weaker signaldue to significantly higher geostationary orbital altitudes (35,786km), which enables imagery with spatial resolution comparableto NPP while providing more frequent updates.ConclusionThe eyes of Suomi NPP have opened our own to visible-light sourcesthat transcend the darkness and understood limitations of nighttimeenvironmental sensing. The capability of the VIIRS/DNB to detectairglow and starlight illumination holds important and immediatepractical implications for climate assessment, weather and hazardsmonitoring, and our ability to observe interactions between thelower and upper atmosphere. The particular value of airglow, traditionally regarded within the astronomy community as a nuisance,seems to reaffirm the old adage that “One man’s trash is anotherman’s treasure.” These findings stand to influence the scope anddesign of next-generation environmental satellite missions.The complex space/time variability of DIM light sources presents unique research challenges for quantitative applications.Whereas contributions from the integrated starlight and zodiacallight will vary with both local observation time and season in predictable ways, contributions from the airglow include the primaryemission. A multisensor approach that incorporates simultaneous,independent observations of the primary airglow emission layermay offer a way to quantify this highly dynamic source.MethodsTo calibrate and quality-control the VIIRS/DNB data, departures from laboratory measurements of the background electronic noise and offset pattern mustbe characterized and removed (40, 41). The offset for the high gain stage ofthe DNB was determined by observing the Pacific Ocean during the newmoon, when the solar zenith angle was at least 105° (15° below the horizon).Only data between 50° south and 50° north latitude were included to excludeillumination from the aurora. A mask was used to exclude areas of knownanthropogenic illumination. Outliers were rejected by using a 3-δ filter.Nighttime imagery examples were produced from Suomi NPP VIIRS/DNBdescending nodes by using data obtained from the NPP Integrated DataProcessing Segment. Only new moon data under astronomical dark (solar andlunar zenith angles > 108°) illumination conditions were considered. Thenoise/offset corrected radiance data were remapped to a Mercator projection, cropped to a maximum satellite zenith angle of 60° to avoid residualedge-of-scan noise patterns, scaled logarithmically between [−11.5, −9.0]log(W·cm−2·sr−1), and plotted by using a linear grayscale color palette.Normalized distributions of DNB radiance for new moon, full moon, anddaytime scenes were based on data collections over the north/central PacificOcean (no land surface reflectance or city light contributions). New moondata were from February 23, 2012 [1404–1422 Coordinated Universal Time(UTC)], full moon from December 7, 2011 (1220–1232 UTC), and daytimefrom March 10, 2012 (2331–2351 UTC). Total samples in each distributionexceeded 17 million. Noise/offset corrections for the new moon and fullmoon data, and a factor of two bit-stripping correction for the daytimeradiances, were applied. The radiance data for all three cases were cropped ata maximum sensor zenith angle of 60° and logarithmically scaled, binned overthe range [−13.0, 0.0] log(W·cm−2·sr−1) at 0.05 increments, and normalized.ACKNOWLEDGMENTS. We thank Kohji Tsumura (Institute of Space andAstronautical Science, Japan Aerospace Exploration Agency), ChristophLeinert (Max Planck Institute for Astronomy), and Joachim Köppen (University of Strasbourg) for insight on nighttime light sources; Jody Russell [ImageScience and Analysis Laboratory, National Aeronautics and Space Administration (NASA)-Johnson Space Center) and Dr. Donald Pettit [NASA, International Space Station (ISS) Astronaut] for assistance with ISS photography;and Jeffrey Cox (Aerospace, Offutt Air Force Base) for assistance with Defense Meteorological Satellite Program datasets. We acknowledge the support of the Naval Research Laboratory through contract N00173-10-C-2003,the Oceanographer of the Navy through the Program Executive Office C4l/PMW-120 under program element PE-0603207N, and the National Oceanicand Atmospheric Administration Joint Polar Satellite System Cal/Val andAlgorithm Program. The views, opinions, and findings in this report arethose of the authors, and should not be construed as an official NOAAand/or US Government position, policy, or decision.1. Ingham MF (1971) The light of the night sky and the interplanetary medium. Rep ProgPhys 34:875–912.2. Roach FE, Gordon JL (1973) The Light of the Night Sky (D. Reidel, Dordrecht, TheNetherlands).3. Leinert Ch, et al. (1997) The 1997 reference of diffuse night sky brightness. AstronAstrophys Suppl Ser 127:1–99.4. Croft TA (1978) Night-time images of the earth from space. Sci Am 239:68–79.5. Croft TA (1973) Burning waste gas in oil fields. Nature 245:375–376.6. Welch R (1980) Monitoring urban population and energy utilization patterns fromsatellite data. Remote Sens Environ 9:1–9.7. Elvidge CD, Baugh KE, Kihn EA, Kroehl HW, Davis ER (1997) Mapping of city lightsusing DMSP Operational Linescan System data. Photogramm Eng Remote Sensing 63:727–734.8. Miller SD, Haddock SHD, Elvidge CD, Lee TF (2005) Detection of a bioluminescentmilky sea from space. Proc Natl Acad Sci USA 102:14181–14184.9. Salomonson VV, Barnes WL, Maymon PW, Montgomery HE, Ostrow H (1989) MODIS:Advanced facility instrument for studies of the Earth as a system. IEEE Trans GeosciRem Sens 27:145–153.10. Lee TF, et al. (2006) The NPOESS/VIIRS day/night visible sensor. Bull Am Meteorol Soc87:191–199.11. Tsumura K, et al. (2010) Observations of the near-infrared spectrum of the zodiacallight with CIBER. Astrophys J 719:394–402.12. Toller GN (1990) Galactic and extragalactic background radiation, optical observations of galactic and extragalactic light: Implications for galactic structure. Proceedings IAU Symposium 139, eds Bowyer S, Leinert Ch (Kluwer, Dordrecht, TheNetherlands), pp. 21–34.13. Hoffman W, Lemke D, Thum C (1997) Balloon-borne infrared telescope for absolutesurface photometry of the night sky. Appl Opt 16:3125–3130.14. Kwon SM, Hong SS, Weinberg JL (1991) Origin and Evolution of Interplanetary Dust,Proceedings IAU Symposium 126, eds Levasseur-Regourd AC, Hasegawa H (Kluwer,Dordrecht, The Netherlands), pp. 179–182.15. Mende SB, Banks PM, Nobles R, Garriott OK, Hoffman J (1983) Photographic observations of Earth’s airglow from space. Geophys Res Lett 10:1108–1111.16. Broadfoot AL, Kendall KR (1968) The Airglow Spectrum, 3100-10,000Å. J Geophys ResSpace Physics 73:426–428.17. Meinel AB (1950) OH emission bands in the spectrum of the night sky. Astrophys J111:555.18. Donahue TM, Guenther B, Thomas R (1973) Distribution of atomic oxygen in theupper atmosphere deduced from Ogo 6 airglow observations. J Geophys Res 78:6662–6689.19. Reed EI, Fowler WB, Blamont JE (1973) An atlas of low-latitude 6300-Å [O I] nightairglow from Ogo 4 Observations. J Geophys Res 78:5658–5675.20. Xu J, et al. (2010) Strong longitudinal variations in the OH nightglow. Geophys ResLett 37:L21801.21. Cogger LL, Elphistone RD, Murphree JS (1981) Temporal and latitudinal 5577 Å airglow variations. Can J Phys 59:1296–1307.22. Takahashi H, Onohara A, Shiokawa K, Vargas F, Gobbi D (2011) Atmospheric waveinduced O2 and OH airglow intensity variations: effect of vertical wavelength anddamping. Ann Geophys 29:631–637.23. Adachi T, et al. (2010) Midnight latitude-altitude distribution of 630 nm airglow in theAsian sector measured with FORMOSAT-2/ISUAL. J Geophys Res 115:A09315.24. Shepherd GG, McLandress C, Solheim BH (1995) Tidal influence on O(1S) airglowemission rate distributions at the geographic equator as observed by WINDII. Geophys Res Lett 22:94GL03052.25. Marsh DR, Smith AK, Mlynczak MG, Russell JM, III (2006) SABER observations of theOH Meinel airglow variability near the mesopause. J Geophys Res 111:A10S05.26. Hersé M (1984) Waves in the OH emissive layer. Science. New Series 225:172–174.27. Mende SB, Swenson GR, Geller SP, Spear KA (1994) Topside observation of gravitywaves. Geophys Res Lett 21:2283–2286.28. Makela JJ, et al. (2011) Imaging and modelling the ionospheric airglow response overHawaii to the tsunami generated by the Tohoku earthquake of 11 March 2011. Geophys Res Lett 38:L00G02.29. Paxton LJ, et al. (1992) SSUSI: An horizon-to-horizon and limb viewing spectrographicimager – UV remote sensing, SPIE International Symposium on Optical Applied Science and Engineering, Ultraviolet Technology IV, SPIE Paper 1764-15.15710 | www.pnas.org/cgi/doi/10.1073/pnas.1207034109 Miller et al.30. Degenstein DA, Llewellyn EJ, Lloyd ND (2003) Volume emission rate tomographyfrom a satellite platform. Appl Opt 42:1441–1450.31. Warnecke G, et al. (1969) Meteorological results from multi-spectral photometry inairglow bands by the OGO-4 satellite. J Atmos Sci 26:1329–1339.32. Walker DE, Schwarz HE, Bustos E (2006) Monitoring the night sky with the CerroTololo all-sky camera for the TMT and LSST projects. Proc SPIE 6267:62672O.33. Taylor MJ, Hapgood MA (1988) Identification of a thunderstorm as a source of short periodgravity waves in the upper atmospheric nightglow emissions. Planet Space Sci 36:975–985.34. Dewan EM, et al. (1998) MSX satellite observations of thunderstorm-generatedgravity waves in mid-wave infrared images of the upper stratosphere. Geophys ResLett 25:939–942.35. Stephens GL (2005) Cloud feedbacks in the climate system: A critical review. J Clim 18:237–273.36. Patrenko B, Ignatov A, Kihai Y, Heidinger A (2010) Clear-sky mask for the advancedclear-sky processor for oceans. J Atmos Ocean Technol 27:1609–1623.37. Lee TF (2000) Nighttime observation of sheared tropical cyclones using GOES 3.9-μmdata. Weather Forecast 15:759–766.38. Ellrod GP (1995) Advances in the detection and analysis of fog at night using GOESmultispectral infrared imagery. Weather Forecast 10:606–619.39. Pavolonis MJ (2010) Advances in extracting cloud composition information fromspaceborne infrared radiances—a robust alternative to brightness temperatures. PartI: Theory. J Appl Meteorol Climatol 49:1992–2012.40. Mills S, et al. (2010) Calibration of the VIIRS Day/Night Band (DNB). American Meteorological Society 6th Annual Symposium on Future National Operational Environmental Satellite Systems-NPOESS and GOES-R, 9.4 (American Meteorological Society,Boston). CD-ROM..41. Jacobson E, et al. (2010) Operation and characterization of the Day/Night Band (DNB)for the NPP Visible/Infrared Imager Radiometer Suite (VIIRS). American MeteorologicalSociety 6th Annual Symposium on Future National Operational Environmental Satellite Systems-NPOESS and GOES-R (American Meteorological Society, Boston), P349.
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