An Introduction to the EUMETSAT Polar System

I am Dieter Klaes, the Programme Scientist of the EUMETSAT Polar System, known as EPS. My background is in meteorology and physics. I worked as a forecast meteorologist in aviation meteorology and general forecasting, so I know the user side and their needs very well. I have 17 years of experience in satellite meteorology and in building systems and software to exploit satellite data. I created the Satellite Data Processing System for the German Armed Forces and coordinated the development of the direct readout software package AAPP (ATOVS and AVHRR Processing Package) for NOAA satellites. I have worked on the EPS Programme at EUMETSAT for the past twelve years, the last seven of them as Programme Scientist.

EPS (the EUMETSAT Polar System) is part of the Global Operational Satellite Observation System (GOSOS), which is under the auspices of the World Meteorological Organisation (WMO). GOSOS consists of operational and research satellites in both polar and geostationary orbits that provide a wealth of information to the global user community for operational meteorology and climate monitoring.

The EPS Programme is EUMETSAT's first polar-orbiting weather satellite programme. It contributes to the Initial Joint Polar System (IJPS) under a cooperation agreement between EUMETSAT and NOAA to provide and improve operational meteorological and environmental forecasting and global climate monitoring services worldwide.

The IJPS program also contributes to and supports the following systems and programs:

Through the Joint Transition Activities agreement signed in 2003, EUMETSAT and NOAA have agreed to provide an operational polar-orbiting service until at least 2019.

EUMETSAT has operated the geostationary Meteosat satellites for over a decade. These images are from the SEVIRI (the Spinning Enhanced Visible and Infrared Imaging Radiometer) instrument on the Meteosat Second Generation geostationary satellite (MSG-1, now known as Meteosat-8).

With Metop and EPS, EUMETSAT has entered the polar satellite era. EUMETSAT is responsible for the mid-morning orbit of the operational polar satellite observation system, whereas NOAA continues to serve the afternoon orbit with NOAA-18 and NOAA-N'.

Satellite data have considerably improved weather prediction, in part because of the information they provide over data-sparse areas. This includes the oceans, which cover almost three-quarters of the earth's surface and most of the Southern Hemisphere.

This graph shows the increase in forecast quality over time, with the quality of forecasts in the Southern Hemisphere now close to that of the Northern Hemisphere.

What is a polar orbit compared to a geosynchronous orbit? And what are the advantages and benefits of polar satellites? In a geosynchronous orbit, the satellites are positioned over the equator at an altitude of about 36000 km. They orbit at exactly the angular speed of the earth's surface, making them appear to stand still over the equator at a given longitude.

A polar orbit is quite different. The satellites fly at lower altitudes (typically about 820 km) and pass close to the poles.

A single polar-orbiting satellite observes the entire globe in 12 hours. Most locations are viewed a minimum of twice daily. Coverage at high latitudes is more frequent due to the overlap by consecutive orbits. The global coverage provided by polar-orbiting satellites makes the data extremely useful for applications such as numerical weather prediction and climate monitoring.

To allow for the routine viewing of a fixed point at about the same local solar time each day, meteorological polar orbiters are placed into sun-synchronous near-polar orbits. Sun-synchronous means that the satellite orbit remains fixed with respect to the sun with the earth rotating under the satellite. A specific satellite will pass overhead at a specific time of day or night, for example, at 9:30 and 21:30 local time at the equator for Metop. A network of polar satellites, such as IJPS, is usually coordinated to cover a specific location at various times of day.

In contrast to polar-orbiting satellites, a single geostationary satellite observes about one-third of the surface of the earth and provides a higher refresh rate. Geostationary satellites, however, cannot observe polar latitudes.

Due to the low flight altitude, polar-orbiter instruments are capable of a higher ground resolution than geostationary satellites. This is especially true in the infrared, and results in higher-resolution imagery and derived products. In meteorological applications, the typical ground resolution of visible and infrared polar satellite imagery ranges from hundreds of meters to about one kilometre.

Polar satellites provide information on the vertical structure of the atmosphere from data-sparse areas, particularly oceans and polar regions. This is critical to NWP, where more than 90% of the data come from satellites.

Because of their low orbit, polar satellites make it possible to provide atmospheric soundings at a ground resolution of some tens of kilometres in both the infrared and microwave regions of the electromagnetic spectrum.

Polar-orbiting satellites offer another distinct advantage over geostationary satellites in that they are able to observe the earth-atmosphere system with microwave sensors. Microwaves penetrate clouds that would otherwise block the satellite's view of the atmosphere as occurs with visible and infrared observations. Microwave remote sensing allows us to probe the interior of clouds and see both the atmosphere and surface below. Microwave sensors operate day and night, as do infrared sensors, and in nearly all weather conditions. In addition, they provide improved coverage of the stratosphere.

While there are important differences between geostationary and polar systems, the two are complementary and together create a comprehensive observation system.

2.0 EPS Programme

The EUMETSAT Polar System (EPS) is a complex programme with many international partners. EPS has both a ground component and a space component. The space component consists of the Metop satellites, which were jointly developed by EUMETSAT and ESA, the European Space Agency.

As mentioned earlier, EUMETSAT is working in partnership with NOAA to provide the Initial Joint Polar System.

The key elements of IJPS are the coordination of polar-orbiting satellites, the exchange of common payload elements, and the processing and sharing of data. A separate agreement was signed in 2003 (the Joint Transition Activities agreement) that extends the cooperation beyond IJPS to provide an operational polar-orbiting service until at least 2019.

The partnership with the French Space Agency CNES (Centre National des Etudes Spatiales) has led to the development of IASI, the Infrared Atmospheric Sounding Interferometer. IASI is a key innovation in the Programme. CNES is also a partner for the Advanced Data Collection System (ADCS).

Another Programme element is the Northern Latitude Command and Data Acquisition Station located on Spitzbergen in the Svalbard Archipelago. Spitzbergen is far enough north (78° N) to receive all 14 orbits a day. The satellites store the measured global mission data of one orbit and then downlink the data when they are in view of the earth receiving station.

EUMETSAT and NOAA exchange data as part of IJPS. NOAA receives all EPS data across a specific transatlantic link, and also gets so-called "blind orbit" data—that is, data from the orbits of NOAA satellites that cannot be seen from the NOAA station at Fairbanks, Alaska. EUMETSAT receives all data from the NOAA afternoon satellites and processes them in their ground segment. The ground segment performs command and control of the spacecraft and is responsible for the reception, processing, and exchange of data, as well as the generation of products.

The WMO community is served by both organisations through the Global Telecommunications System (GTS), a dedicated global network for the telecommunication of meteorological data and products.

As you've heard, the EPS space segment consists of the Metop satellites, which are composed of payload and service modules as well as a solar array. The payload module hosts twelve instruments, of which eight are meteorological.

The Metop satellites fly in a sun-synchronous orbit at an average altitude of about 820 km, crossing the equator at 9:30 Local Solar Time in the descending node. There will be three Metop satellites, providing uninterrupted service in the same orbit over at least a 14-year period.

You may hear products referenced as day 1 or day 2. Day 1 products are those that form the baseline of the EPS development, i.e., they have been specified as mandatory in the EPS System Requirements, and the System is committed to providing them.

Day 1 products consist of the central processing Level 0 and Level 1 global products from each instrument and selected Level 2 products, including:

Day 2 products are those that have been added since the system was successfully commissioned. Examples include soil moisture products from ASCAT data for use in NWP, global Normalized Difference Vegetation Index or NDVI, and polar cap winds. All of these products are based on EPS End User Requirements. Note that the decentralised Satellite Application Facilities produce a wealth of Level 2 products and those at higher levels.

3.0 Innovations and Benefits

Here are the instruments on the Metop satellite. There are two major sounding systems:

Here is the front end of Metop with the six folded antennas of the Advanced Scatterometer (ASCAT). ASCAT's primary mission is to measure ocean surface wind vectors.

The Global Ozone Monitoring Instrument (GOME-2) is used to monitor total ozone, ozone profiles, and other trace gases.

Finally, here's one of the three antennas of the GNSS Receiver for Atmospheric Sounding (GRAS). (GNSS stands for Global Navigation Satellite System.) GRAS provides profiles of temperature and humidity at high vertical resolution.

Now we're getting to the major technical innovation of the Metop/EPS system and basically the main reason for the Metop satellites, that is, the Infrared Atmospheric Sounding Interferometer, known as IASI . IASI is a spectrometer—a so-called Fourier Transform Spectrometer (FTS) or, to be more precise, a Michelson Interferometer.

IASI measures energy emitted by the earth-atmosphere system in the infrared portion of the electromagnetic spectrum at high spectral resolution (8461 "channels") to provide improved profiles of atmospheric temperature and moisture and to monitor trace gases.

IASI provides a quantum leap in infrared sounding capabilities from space, which will have a significant impact on numerical weather prediction. The considerable progress in NWP over the last two decades has been due, in part, to the use of satellite sounding information in the data assimilation step.

As you've heard, more than 90% of the data entering NWP come from satellites. One of the primary motivations for developing IASI was to provide increased accuracy that would help improve the input for NWP models.

4.0 Infrared Atmospheric Sounding Interferometer (IASI)

IASI is the largest and heaviest instrument on the Metop satellite and is provided by the French Space Agency CNES. CNES also provides the operational Level 1 processing software for the Core Ground Segment and has a technical expertise center (known as IASI TEC) in Toulouse that analyzes instrument performance.

The cross section shows a baroclinic structure generated in the remnants of Hurricane Floyd. The hurricane was responsible for a major storm in the United Kingdom and Brittany, resulting in major damage and loss of lives. The feature was not analysed by the forecast model, and the storm was not correctly predicted.

This example illustrates what needs to be measured and input into NWP models. Vertical temperature information should be provided at 1 K/km resolution and about 25 km horizontal sampling. Relative humidity should be provided with an accuracy of about 10%.

Since meteorological features like tropical cyclones occur mostly over oceans, we must rely on satellite data to provide this information.

IASI was developed in response to the need to observe the atmosphere in greater detail, employing sensors that measure energy in a large number of narrow spectral channels. This approach to remote sensing is also commonly referred to as hyperspectral sounding.

IASI processes raw observations into calibrated spectra on board the Metop satellite, which are sent to the ground as Level 0 data.

During Level 1 processing, AVHRR radiances are analysed within one IASI field of view (FOV) to obtain the location of clouds in the FOV.

IASI has an integrated imaging radiometer, which provides 64 x 64 pixel images in the IR window region (10.5 –12 µm) in the same focal plane as the sounding radiances.

The imager serves to align the AVHRR information to the IASI FOV. AVHRR is also used to navigate the IASI pixels.

The integrated imager provides a sampling of better than 1 km for infrared scenes, which are collocated with the AVHRR images.

During Level 2 processing, a determination is made as to whether a cloud clearing or cloudy retrieval will be performed. Cloud clearing implies that you can get an atmospheric profile down to the ground even when the IASI scene/FOV is not totally "clear."

IASI Level 1 spectra for all 8461 channels are disseminated to users via the EUMETCast service. A subset of 300 channels is transmitted over the GTS system. Both datasets are made available in the standardized BUFR format.

IASI Level 2 products are derived via a complex process that uses the full spectral information of the IASI instrument, supplementary information from the ATOVS and AVHRR instruments, and input from NWP data.

The Level 2 product suite typically used by the forecaster and climate communities includes:

Keep in mind that the product suite is modified when there is cloud coverage, and that data quality information is delivered with the products.

This picture shows an example for a single retrieval at midlatitudes, derived with the IASI Level 2 algorithm from synthetic data. A temperature profile is shown on the left, a humidity profile on the right. The retrieved quantities (red) are displayed together with the true state (green).

Validation efforts involving measurements from NASA's hyperspectral sounder, AIRS, have demonstrated that IASI Level 2 processing is meeting user requirements. The graphics compare IASI temperature and dewpoint profiles with profiles obtained from an ECMWF analysis and collocated radiosonde observations. Good agreement is achieved.

The infrared spectrum has absorption lines for trace gases that play a role in monitoring volcanic activity. This picture from an October 2002 eruption of the Mt. Etna volcano shows the aerosol and sulphur dioxide (SO₂) plumes in the wake of the eruption. The data were derived from the AIRS instrument.

Volcanoes can produce large SO₂ concentrations over limited regions and for relatively short time periods. The most common sources of SO₂ are fuel combustion for power generation for use in homes, industry, and transportation.

N₂O is a product of burning fossil fuels and other organic matter and is also naturally emitted from soils and oceans. It is the third most important greenhouse gas as well as a component in the ozone cycle.

The most common sources of carbon monoxide include motor vehicles and various industrial processes. It contributes to the formation of ground-level ozone and smog in urban areas. Carbon monoxide harms our health by reducing the amount of oxygen available to body organs and tissues.

Carbon dioxide is a major component of the carbon cycle. Its most common sources include volcanic outgassing, the combustion of organic matter, and the respiration by living organisms (plants and animals). CO₂ plays a key role in the Earth's greenhouse effect and is a major focus of the debate on global warming and climate change.

IASI data will be used to produce a methane columnar amount. The product displayed was generated by a study within the IASI Sounding Science Working Group from IMG Interferometer data. (IMG stands for Interferometer Monitor for Greenhouse Gases.) The Interferometer flew on the Japanese ADEOS satellite.

Methane is an important greenhouse gas and accounts for approximately 20% of the total warming effect of all greenhouse gases combined.

This image shows an example of the total column ozone from 1 to 10 April 1997. This is one of two ozone products, and was produced by the IASI Sounding Science Working Group (ISSWG) using IMG Interferometer data.

Ozone plays an important role in the Earth's stratosphere by absorbing harmful ultraviolet radiation from the Sun. At high concentrations near ground level, however, ozone is considered a pollutant that can cause respiratory health problems for humans and damage plants and ecosystems.

5.0 ATOVS, MHS, AVHRR Heritage Sounding Instruments

One aspect of running an operational satellite system is to provide continuity with previous systems and ensure coherence between the various components of the system. ATOVS and the AVHRR imager were originally developed for the sounding of temperature and moisture for the NOAA satellites using the TIROS-N system and the NOAA-KLM series.

The ATOVS suite includes the HIRS/4, AMSU-A, and Microwave Humidity Sounder (MHS) instruments. In addition to flying on the NOAA satellites, both ATOVS and AVHRR are on Metop as part of IJPS.

Bear in mind that microwave instruments provide near-all-weather sounding capability.

Global ATOVS and AVHRR Level 1 products are provided to users from the central facility.

A Level 2 product containing ATOVS-derived vertical profiles of temperature and humidity will be produced as well.

EUMETSAT may provide an expanded product suite in its central facility or within the Satellite Application Facilities.

The following is a list of potential products. Note that sea ice and precipitation products are already provided by the SAF's.

Using microwave and infrared sounders in combination, we can derive column-integrated atmospheric water vapour, also known as total precipitable water (TPW), over land and ocean.

These measurements are vital for understanding the global hydrologic cycle. TPW is an important parameter in short-term weather prediction, including the analysis of tropical cyclone intensity trends, identification of atmospheric frontal boundaries, forecasting heavy precipitation, and data assimilation for numerical models. Water vapour also impacts atmospheric chemistry and pollution, transport, and climate trend monitoring. It also plays a key role in the ongoing debate over future climate change.

Research scientists use cloud liquid water (CLW) estimates to assess the properties of stratiform clouds. Forecasters can use cloud liquid water to help assess the potential for aircraft icing.

Using microwave imagery to monitor the concentration, extent, age, and thickness of sea ice is important for:

Microwave rain rate is a derived product useful for monitoring precipitation worldwide. Space-based precipitation estimates supplement land-based rain gauge and radar observations across Earth's vast, data-sparse oceanic regions and remote land areas. Knowledge of the spatial and temporal aspects of precipitation is important to our understanding and monitoring of the global hydrologic cycle. Space-based precipitation estimates in near-real-time also benefit short-term weather forecasting by providing critical information on potentially hazardous precipitation events beyond the range of land-based observing systems.

Products that monitor global snow and ice cover can be derived from microwave radiometers. Microwave observation is especially important at higher latitudes, including polar regions, where visible and infrared sensing can be limited due to cloud cover and long periods of darkness.

Another strength of microwave observations is the ability to probe beneath the surface of snow and ice, and reveal properties such as snow water equivalent and ice age. Characterizing snowpack and ice is important for:

The Microwave Humidity Sounder (MHS) was developed by EUMETSAT as a replacement for the AMSU-B instrument in the ATOVS suite. MHS was the first instrument in polar orbit developed by EUMETSAT and became part of the payload of the first IJPS satellite in orbit, NOAA-18, launched 20 May 2005. This provided EUMETSAT with valuable experience, which was applied to the new instruments flying on Metop.

The images show a scene acquired 31 May 2005 covering the North Atlantic down through portions of Europe and North Africa.

We see the surface and clouds in the two images taken with channels 1 and 2. Notice the Vatna glacier on Iceland.

The next three images show an increased sensitivity to water vapour, cloud ice, and precipitation-sized hydrometeors. Channels with increasing sensitivity to water vapour see energy emitted from layers higher in the atmosphere. Notice that the Vatna glacier, which extends to 2199 meters above sea level, is still visible in channel 5.

Measurements taken with the MHS are critical in deriving profiles of atmospheric moisture and for quantifying precipitation.

6.0 ASCAT Ocean Winds

Metop has two heritage instruments from the European Remote-Sensing Satellite (ERS), which form part of the ESA research missions, ASCAT and GOME-2. ASCAT provides observations of surface wind over the oceans, whereas GOME monitors ozone and trace gases.

ASCAT is the only active remote sensing instrument on Metop. An active sensor transmits and then listens to the return energy as opposed to a passive sensor, which only listens to emitted energy. ASCAT is a C-band radar in the heritage of the Active Microwave Instruments (AMI) successfully flown on the ESA ERS satellites. The main mission objective is to derive wind vectors over the ocean surface.

This first view shows swath coverage available with the heritage ERS scatterometer.

With the newer ASCAT instrument, we observe data over two swaths instead of one, with each swath being wider than with ERS. Note that ASCAT wind products will be available at both 25-km and 12.5-km resolution.

This plot shows ocean observation coverage for 12 hours, which is much improved with the addition of a second swath.

Plot showing 12 hour ASCAT scatterometer global coverage.

Ocean surface wind vectors have already demonstrated their value in the meteorological analysis of important weather features. The two examples show wind vectors over the North Atlantic from 13 April 2006.

In the first plot, we can see diminished wind speeds downwind of Iceland.

Plot of ERS-2 ocean surface wind vectors over north Atlantic Ocean showing blocking of winds downwind of Iceland.

The second plot highlights a confluence pattern and indicates the presence of a frontal zone.

Plot of ERS-2 ocean surface wind vectors over north Atlantic Ocean showing confluence pattern associated with a frontal zone.

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6.3 ASCAT Soil Moisture Product

Research activities have revealed a number of emerging applications based on scatterometer data that go beyond the "classical" derivation of wind vectors. One is the estimation of soil moisture, which is needed for NWP and is of interest to ground transportation. Satellites provide high-resolution coverage that could not be provided by the sparse ground measurement networks. The scatterometer makes it possible to map soil moisture, and will be available as a day 2 product for EPS.

ASCAT Soil Moisture products over Europe contrasting dry versus wet seasons for 1996

ASCAT Soil Moisture products over Europe contrasting dry versus wet seasons for 2000

Shown here is a typical soil moisture product derived from ERS data for January of two different years. Notice both the dramatic differences in soil moisture content across Europe for a given month, and the dramatic changes between 1996 and 2000.

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7.0 GOME-2 Atmospheric Chemistry Products

7.1 Global Ozone Monitoring Experiment (GOME-2)

Now let's look at the second heritage instrument on Metop, the GOME-2. Together with IASI, the GOME-2 provides the capability to monitor the total column ozone, ozone profiles, and trace gases. The information is useful for climate monitoring, atmospheric chemistry, the ozone cycle, and the radiation budget. The data will also aid in the monitoring and prediction of damaging UV radiation and the forecasting of volcanic cloud displacement. Ozone patterns can be used in NWP as tracers to derive stratospheric winds.

Metop satellite and instruments.

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7.2 GOME-2 Level 1 Products — Measurement Spectra

GOME is a spectrometer that measures the backscattered ultraviolet and visible radiation from the earth/atmosphere system.

Illustration showing how GOME senses direct and indirect sunlight for monitoring total atmospheric ozone content

A reference spectrum is taken from the incoming solar radiation. Measurements are made in four spectral bands to retrieve amounts of both ozone and other trace gases. The four bands are indicated in different colours.

The figure summarizes the GOME-2 measurements and shows the potential trace gases that may be detected. This example shows spectra for both the incoming solar radiation and the backscattered UV and visible radiation (sometimes known as the Earthshine spectrum).

Metop GOME-2 spectral coverage and potential atmospheric trace gas products.

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7.3 GOME Level 2 Products (Part 1)

The total ozone column amount is generated by the Ozone Monitoring Satellite Application Facility. The animation shows the Southern Hemisphere ozone hole and its development during October 2002, illustrated by the total ozone amount.

Animation of GOME Level 2 Total Column Ozone product.

Click to view animation

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7.4 GOME Level 2 Products (Part 2)

Other trace gas products are expected to be derived from the GOME-2 data. The example shows high concentrations of nitrogen dioxide (NO₂) over densely populated and industrialised areas. NO₂ is a greenhouse gas, an important pollutant, and a contributor to the ozone cycle. It can cause respiratory problems from high concentrations or long exposure and contributes to the formation of acid rain, nutrient overload that diminishes water quality, reductions in visibility, and production of other toxic chemicals.

GOME Level 2 product example of column density nitrogen dioxide as seen with the ERS-2 GOME instrument.

As mentioned earlier, sulphur dioxide is another important trace gas often associated with volcanic eruptions. Exposure to high levels of SO₂ can aggravate respiratory problems. Sulphate particles also result in haze and are a major cause of reduced visibility. SO₂ reacts with other substances to form acids that fall to earth as acid rain, fog, snow, and even dust. Acid rain damages buildings, painted surfaces, forests, crops, rivers and lakes, and can have long-term impacts on plant and animal ecosystems.

The images show eruptions of Mount Etna in Sicily on two dates in July 2001. Notice the extent of SO₂ plumes emitted from the volcano. Data like these can be used as a basis for predicting the displacement of volcanic clouds, if they are used in dispersion models with a forecast model.

GOME Level 2 product example, column density sulfur dioxide from the Mt. Etna volcano as seen with the ERS-2 GOME-1 instrument.

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8.0 GRAS — Using Satellites for Atmospheric Sounding

8.1 GNSS Receiver for Atmospheric Sounding (GRAS)

There is another innovative sounding system on the Metop Satellite (the GRAS instrument), which provides the first operational use of Global Positioning System (GPS) satellites for atmospheric sounding. GRAS uses GPS signals to provide profile information of temperature and humidity at high vertical resolution (potentially better than 1 km). This will be particularly beneficial for NWP and climate monitoring.

Metop satellite and instruments.

There are about 24 GPS satellites orbiting around the Earth, all in high-altitude orbits (about 20200 km).

An occultation occurs for GRAS whenever a GPS satellite rises or sets and is no longer in direct line of sight of the GRAS instrument. Despite this, the signal from the GPS transmitter still reaches the GRAS instrument as it passes through the limb of the atmosphere and is refracted. A single GRAS instrument in near-polar orbit at 824 km will observe over 500 occultations per day, distributed quite uniformly over the globe.

When GRAS was first introduced as a payload, it was clear that a complete system beyond the GPS and Metop satellites was needed. Since several spacecraft are involved, each with a set of onboard clocks, time-based errors can contribute to errors in the measurements. With a ground-based set of reference stations, the satellites used for an occultation measurement can be seen from the stations simultaneously, eliminating clock errors through differencing. With approximately 24 stations world-wide, redundancy is about 200%, which ensures operational availability. In addition, the precise orbits for each spacecraft need to be known in real time.

We're looking at the signal of a GPS satellite as it is received by the research system GPS-MET. Note the change of the signal-to-noise ratio, which decreases as the signal descends deeper into the troposphere. GRAS is expected to have a better signal-to-noise ratio and provide reliable profiles that extend deeper into the troposphere.

As they travel through the atmosphere, GPS signals are bent due to the change in density, which is, in turn, a function of temperature and moisture. This relationship is described by the refractive index.

GRAS measures the phase delay of the signal caused by the bending of the signal ray.

The amount of bending, known as the bending angle, is then derived from the phase data, resulting in the Level 1 bending angle product. By integrating this information with an a priori knowledge of either temperature or moisture, the combined temperature moisture profile can be extracted. The GRAS Level 1 product is the vertical profile of the bending angle. The product also contains total electron content.

The Level 1 product is transmitted to both users and the GRAS Meteorology SAF, where the Level 2 vertical profiles are retrieved. The figure shows an example of bending angles and the retrieved temperature profile derived during the development phase of the operational GRAS processing system using Champ occultation data.

9.0 EPS Services

EPS provides a number of services, ranging from the provision of global products to the support of humanitarian search and rescue missions.

10.0 Webcast Summary

EPS assures continuity to the current global observing system through the continuation of the proven ATOVS instrument suite and the AVHRR imager. In addition, highly innovative features have been implemented with EPS:

References

The following resources provide additional information on the topics presented in this Webcast.

Carn, S.A., L.L. Strow, S. de Souza-Machado, Y. Edmonds, and S. Hannon, 2005: Quantifying tropospheric volcanic emissions with AIRS: The 2002 eruption of Mt. Etna (Italy). Geophys. Res. Let., 32, 5 pp.

Chahine, M., Y. Yung, Q. Li, E. Olsen, L. Chen, and N. Krakauer, 2006: AIRS CO2 retrievals using the method of vanishing partial derivatives (VPD). Presentation, AIRS Science Team Meeting, Caltech, Pasedena, CA. [Available online at
http://www-airs.jpl.nasa.gov/Science/ResearcherResources/MeetingArchives/TeamMeeting20060307/ ; 2006]

Clerbaux, C., J. Hadj-Lazaro, S. Turquety, G. Megie, and P.-F. Coheur, 2003. Trace gas measurements from infrared satellite for chemistry and climate applications. Atmos., Chem. Phys., 3, 1495-1508.

EPS Brochures, EUMETSAT, Darmstadt, Germany. [Available online at http://www.eumetsat.int; 2006; found under "Publications" > "Brochures"]

EPS Product Guides, EUMETSAT, Darmstadt, Germany. [Available online at http://www.eumetsat.int; 2006; found under "Publications" > "Technical and Scientific Documentation" > "EPS Product Guides"]

Rabier, F., E. Klinker, P. Courtier, and A. Hollingsworth, 1996: Sensitivity of forecast errors to the initial conditions, Quart. J. Roy. Meteor. Soc., 122, 121-150.

Turquety, S., J. Hadji-Lazaro, C. Clerbaux, D.A. Hauglustaine, S.A. Clough, V. Casse, P. Schlüssel, and G. Megie, 2004: Operational trace gas retrieval algorithm for the Infrared Atmospheric Sounding Interferometer. J. Geophys. Res., 109, 19 pp.

Turquety, S., J. Hadji-Lazaro, and C. Clerbaux, 2002: First satellite ozone distributions retrieved from nadir high-resolution infrared spectra. Geophys. Res. Lett., 29, 51-1 to 51-4.

Links

Welcome to the links section of the EPS Webcast. We have gathered links of interest to users of MetOp and other polar-orbiting satellite platforms. These links include more information on polar-orbiting satellites, data, derived products, applications, processing systems, and related training and education resources. (By following these links you will be leaving the EPS Webcast.)

EPS Polar System Home Page
(From the EUMETSAT home page, look under "What We Do" > "Satellites" > "EUMETSAT Polar System".)
Visit EUMETSAT’s Web site to view information, documentation, and visualizations on EUMETSAT’s first polar-orbiting operational meteorological satellite system, the EUMETSAT Polar System (EPS). This page also provides links to additional resources on EPS benefits, services, training and education, program background, presentations, and more in-depth technical documentation.

ESA MetOp Home Page
This European Space Agency (ESA) Web site hosts a wealth of information, documentation, and visualizations on the EUMETSAT Polar System (EPS).

COMET^® Program Polar-Orbiting Satellite Resource Links
This Web page on the NPOESS Userport Web site contains links of interest to users of NOAA and other polar-orbiting satellite platforms with an emphasis on operational forecasting. Links to real-time data and products, news and information, and relevant documentation are included.

NOAA/NESDIS IJPS Home Page
This Web site is hosted by the U.S.’ NOAA/NESDIS and provides information on the cooperative effort between NOAA and EUMETSAT known as the Initial Joint Polar-orbiting Operational Satellite System (IJPS). The goal of IJPS is to ensure coordination of two polar-orbiting satellites systems to provide and improve operational meteorological and environmental forecasting and global climate monitoring services worldwide.

WMO Space Program Home Page
This Web page is a portal to technical, science, training and education information related to various geostationary and polar-orbiting meteorological satellite programs and systems around the world.

WMO Virtual Laboratory for Satellite Training and Data Utilization
This site contains links to the WMO Virtual Laboratory which is a Web portal that organizes resources and information on training activities for forecasters and other users of operational meteorological satellite data and products across the globe. The Virtual Laboratory is a collaborative effort joining major satellite operators and WMO “centers of excellence” at WMO Regional Meteorological Training Centers that are distributed around the world.

Contributors

Project Sponsors
European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT)
European Space Agency (ESA)
Centre National d'Etudes spatiales (CNES)

Sponsors
National Oceanic and Atmospheric Administration (NOAA)
National Weather Service (NWS)
Naval Meteorology and Oceanography Command (NMOC)
Air Force Weather Agency (AFWA)
National Environmental Satellite Data and Information Service (NESDIS)
National Polar-orbiting Operational Environmental Satellite System (NPOESS)
Environment Canada -Meteorological Service of Canada (MSC)
Australian Bureau of Meteorology (BoM)

Principal Science Advisor
Dr. Dieter Klaes (EUMETSAT)

Associate Science Advisors
Patrick Dills – UCAR/COMET
Volker Gärtner – EUMETSAT

Project Leads
Patrick Dills – UCAR/COMET
Marianne Weingroff – UCAR

Instructional Design
Marianne Weingroff – UCAR

Computer Graphics/Interface Design
Steve Deyo – UCAR/COMET
Heidi Godsil – UCAR/COMET

Multimedia Authoring/Additional Instructional Design
Carl Whitehurst – UCAR/COMET

Audio Editing/Production
Seth Lamos – UCAR/COMET

Audio Narration
Dr. Dieter Klaes (EUMETSAT)

Software Testing/Quality Assurance
Mike Smith – UCAR/COMET

Copyrights Administration
Mike Smith – UCAR/COMET

COMET HTML Integration Team 2021

Tim Alberta — Project Manager
Dolores Kiessling — Project Lead
Steve Deyo — Graphic Artist
Ariana Kiessling — Web Developer
Gary Pacheco — Lead Web Developer
David Russi — Translations
Tyler Winstead — Web Developer

COMET Staff, 2006:

Director
Dr. Timothy Spangler

Deputy Director
Dr. Joe Lamos

Business Manager/Supervisor of Administration
Elizabeth Lessard

Administration
Lorrie Alberta
Hildy Kane
Linda Korsgaard

Graphics/Media Production
Steve Deyo
Heidi Godsil
Seth Lamos

Hardware/Software Support and Programming
Tim Alberta (IT Manager)
James Hamm
Karl Hanzel
Ken Kim
Mark Mulholland
Dan Riter
Carl Whitehurst
Malte Winkler (student)

Instructional Design
Patrick Parrish (Production Manager)
Dr. Alan Bol
Lon Goldstein
Dr. Vickie Johnson
Bruce Muller
Dwight Owens
Dr. Sherwood Wang

Meteorologists
Dr. Greg Byrd (Project Cluster Manager)
Wendy Schreiber-Abshire (Project Cluster Manager)
Dr. William Bua
Patrick Dills
Tom Dulong
Kevin Fuell
Dr. Stephen Jascourt
Matthew Kelsch
Dolores Kiessling
Dr. Arlene Laing
Elizabeth Mulvihill Page
Dr. Doug Wesley

Software Testing/Quality Assurance/Copyrights Administration
Michael Smith (Coordinator)

Spanish Translations
David Russi

NOAA/National Weather Service - Forecast Decision Training Branch
Anthony Mostek (NWS COMET Branch Chief [acting] and Satellite Training Leader)
Dr. Richard Koehler (Hydrology Training Lead)
Brian Motta (IFPS Training)
Dr. Robert Rozumalski (SOO Science and Training Resource [SOO/STRC] Coordinator)
Shannon White (AWIPS Training)

Meteorological Service of Canada Visiting Meteorologists
Phil Chadwick
James Cummine

An Introduction to EUMETSAT Polar System

Table of Contents

Learning Objectives

1.0 Introduction

2.0 EPS Programme

3.0 Innovations and Benefits

4.0 Infrared Atmospheric Sounding Interferometer (IASI)

5.0 ATOVS, MHS, AVHRR Heritage Sounding Instruments

6.0 ASCAT Ocean Winds

7.0 GOME-2 Atmospheric Chemistry Products

8.0 GRAS — Using Satellites for Atmospheric Sounding

9.0 EPS Services

10.0 Webcast Summary

References

Links

Contributors

COMET HTML Integration Team 2021