earth science

MetOp

MetOp is a earth science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand MetOp rather than just read about it. In short: MetOp (Meteorological Operational satellite) is a series of three polar-orbiting meteorological satellites developed by the European Space Agency (ESA) and operated by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). The satellites form the space segment component of the overall EUMETSAT Polar System (EPS), which in turn is the European half of the EUMETSAT / NOAA Initial Joint…

Key takeaways

MetOp belongs to earth science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect MetOp to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of MetOp from memory before moving on to harder problems.

Reference excerpt

MetOp (Meteorological Operational satellite) is a series of three polar-orbiting meteorological satellites developed by the European Space Agency (ESA) and operated by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). The satellites form the space segment component of the overall EUMETSAT Polar System (EPS), which in turn is the European half of the EUMETSAT / NOAA Initial Joint Polar System (IJPS). The satellites carry a payload comprising 11 scientific instruments and two which support Cospas-Sarsat Search and Rescue services. In order to provide data continuity between MetOp and NOAA Polar Operational Environmental Satellites (POES), several instruments are carried on both fleets of satellites. MetOp-A, launched on 19 October 2006, was Europe's first polar orbiting satellite used for operational meteorology. With respect to its primary mission of providing data for Numerical Weather Prediction, studies have shown that MetOp-A data was measured as having the largest impact of any individual satellite platform on reducing 24-hour forecasting errors, and accounted for about 25% of the total impact on global forecast error reduction across all data sources. A 2023 report updated this estimate stating that the primary MetOp satellite has decreased in relative terms since 2011 from 24.5% to 11.15% in the FSOI metric. Each of the three satellites were originally intended to be operated sequentially, however good performance of the MetOp-A and MetOp-B satellites mean there was a period of all three satellite operating. EUMETSAT lowered the orbit of MetOp-A and decommissioned the spacecraft in November 2021 The successor to the MetOp satellites is MetOp-SG. The first MetOp SG-A1 satellite was launched on 13 August 2025 2:37 CEST (12 August 21:37 local time) from Guiana Space Centre.

Instruments

The following instruments are flown on board the MetOp satellites:

Shared instruments The following instruments are shared on the NPOES satellites which form the U.S. contribution to IJPS:

AMSU-A1/AMSU-A2 – Advanced Microwave Sounding Units HIRS/4 – High-resolution Infrared Radiation Sounder (N.B. Not included on MetOp-C) AVHRR/3 – Advanced Very High Resolution Radiometer Argos A-DCS – Advanced Data Collection System SEM-2 – Space Environment Monitor SARP-3 – Search And Rescue Processor (N.B. Not included on MetOp-C) SARR – Search And Rescue Repeater (N.B. Not included on MetOp-C) MHS – Microwave Humidity Sounder

MetOp specific instruments The following instruments are flown exclusively on the MetOp satellites:

IASI – Infrared Atmospheric Sounding Interferometer GRAS – Global Navigation Satellite System Receiver for Atmospheric Sounding ASCAT – Advanced SCATterometer GOME-2 – Global Ozone Monitoring Experiment-2

Background MetOp has been developed as a joint undertaking between the European Space Agency (ESA) and European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). Recognising the growing importance of Numerical Weather Prediction (NWP) in weather forecasting, MetOp was designed with a suite of instruments to provide NWP models with high resolution global atmospheric temperature and humidity structure. Data from MetOp are additionally used for atmospheric chemistry and provision of long term data sets for climate records.

MetOp heritage The MetOp satellites have a modular construction, comprising a Service Module, a Payload Module and a suite of instruments. A SPOT heritage service module provides power (via solar array and five batteries for eclipse), attitude and orbit control, thermal regulation and Tracking, Telemetry and Command (TT&C). An Envisat heritage payload module provides common command and control and power buses for the instruments along with science data acquisition and transmission. The suite of instruments are largely derived from precursors flown on the European Space Agency's European Remote-Sensing Satellite ERS / Envisat satellites or are fully recurrent units originally developed for NOAA's Television Infrared Observation Satellite (TIROS) series of polar-orbiting satellites.

Data acquisition

With the exception of Search and Rescue (SARSAT), which is a purely local mission with its own dedicated transmitter, all data from the MetOp Instruments are formatted and multiplexed by the Payload Module and either stored on a solid-state recorder for later transmission via an X-Band antenna, or directly transmitted to local users via Advanced High Resolution Picture Transmission (AHRPT) L-Band antenna. The main Command and Data Acquisition (CDA) head is located at Svalbard Satellite Station in Norway. The high latitude of this station allows the global data stored in the solid state recorder of each satellite to be dumped via X-Band once per orbit. Each MetOp satellite produces approximately 2 GB of raw data per orbit. Additionally, in order to improve timeliness of products, one of the operational satellites dumps the data from the descending part of the orbit over the McMurdo Station in Antarctica. Data are then trickle fed from the ground stations to EUMETSAT Headquarters in Darmstadt, Germany, where they are processed, stored and disseminated to various agencies and organisations with a latency of approximately 2 hours without the McMurdo ground station and 1 hour with Svalbard. AHRPT is used to provide a real-time direct readout local mission via a network of receivers on ground provided by cooperating organisations. Data from these stations is also transmitted to EUMETSAT and redistributed to provide a regional service with approximately 30 minutes latency. Due to radiation sensitivity of the AHRPT hardware, the MetOp-A AHRPT did not operate over the polar regions or South Atlantic Anomaly.

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with MetOp

Start with the simplest possible case. Write down what MetOp claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In earth science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to MetOp before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about MetOp ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of MetOp

In research: MetOp appears in earth science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses MetOp in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: MetOp is common in secondary-school and first-year university syllabi. It links to neighbouring topics Argos (satellite system), Earth observation satellites of the European Space Agency, European Organisation for the Exploitation of Meteorological Satellites, so understanding it makes those chapters shorter.
In everyday life: Look for MetOp outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study MetOp in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what MetOp means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain MetOp out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is MetOp in simple terms?

Why does MetOp matter?

Because it connects several earth science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study MetOp?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on MetOp.