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Europe's first geostationary sounder satellite is launched

• 41 Comments
• Only tangentially related: I have nothing but respect for EUMETSAT and their public data store. For past work projects I've had to interface with a pretty broad sample of the world's space and/or meteorological agency's public data stores and APIs and EUMDAC (EUMETSAT's API client) was top tier. Well documented, modern, fast, and generally headache free.
  In fact, I have nothing but respect for any agency that makes free and public access to earth observation data a priority, regardless of how janky their API is.

  By themisto 14 hours ago

• Shout-out to the NOAA GFS team, who publish the GFS analysis directly to AWS S3.
  https://registry.opendata.aws/noaa-gfs-bdp-pds/

  By brandmeyer 6 hours ago

• GFS outputs are also available for free from NOMADS. That was true long before AWS came up with the public dataset program.

  By ccgreg 28 minutes ago

• I've worked with similar data in the past. As you say, nothing but respect for agencies that make such useful data publicly available.
  Are there any other standout national agencies you've dealt with?
  And, have you seen any degradation recently with NOAA data? NGS has always impressed me, but I've been worried about their future lately.

  By nullhole 7 hours ago

• Copernicus browser allows to browser images of the earth in quite high resolution (I think up to 20x20m) refreshed every 3 days or so and it's absolutely cool to be able to use different views such as nir, swir...

  By amarcheschi 8 hours ago

• > MTG-S1 is the first geostationary meteorological sounder satellite to fly over Europe
  I was confused for a minute on how it's both _geostationary_ and _over Europe_ -- you can't be geostationary if your orbit is not over the equator!
  Turns out[1] the MTG-S1 satellite is in fact geostationary and parked at exactly 0°00'00"N 0°00'00"E (off the coast of Ghana), 42164 km up from the center of Earth, it's just pointing at Europe at an angle.
  1 - https://space.oscar.wmo.int/satellites/view/mtg_s1

  By abra0 9 hours ago

• I had doubts about the "parked at exactly 0°00'00"N 0°00'00"E", thinking it was over Null Island just because the data wasn't updated yet and it was showing uninitialized values.
  But you are right, [1] confirms "0° longitude".
  [1] https://user.eumetsat.int/resources/user-guides/mtg-in-opera...

  By progbits 8 hours ago

• NOAA/NASA (USA), EUMETSAT (European organization), JMA (Japan), KMA (Korea), and CMA (China) all have a geostationary satellite (one or more actually). So, northern hemisphere countries, but the coverage is global thanks to the fact that you need to be, as you say, above the equator.

  By complex_pi 9 hours ago

• I am surprised they would pick 0 for the latitude, it seems that most of Europe, whether it's the land or the people is east of that. Maybe some important weather systems develop over the Atlantic and they want to track that?

  By thmsths 8 hours ago

• It’s exactly that. In fact, information propagates along with the winds. If you don’t observe upstream, you instead propagate an information hole. Each new model run incorporates the output of the previous run to preserve sparse weather information. It’s not that there are few observations, it’s that Earth is really big.

  By labster 4 hours ago

• [deleted]

  By 6 hours ago

• > "MTG-S1’s Infrared Sounder will scan nearly 2,000 thermal infrared wavelengths every 30 minutes to build vertical profiles of temperature, humidity, and trace gases. These data will be crucial for detecting fast-developing convective weather by revealing sudden shifts in instability, moisture, or wind – even before clouds begin to form."
  In other words, it is
  > "The Infrared Sounder on MTG-S1 is the first hyperspectral sounding instrument in geostationary orbit."
  https://www.esa.int/Applications/Observing_the_Earth/Meteoro...
  Is there a more technical article describing this hyperspectral instrument somewhere? It sounds pretty novel.
  edit: Also, I'm now confused about the ESA's claim to be "the first", because
  > "In 2016, the Chinese Meteorological Agency (CMA) launched the Geostationary Interferometric Infrared Sounder (GIIRS), to be the first hyperspectral sounder in geostationary orbit"
  https://www.aos.wisc.edu/aosjournal/Volume38/Loveless_PhD.pd... (PhD thesis of David M. Loveless (2021))

  By perihelions 14 hours ago

• > edit: Also, I'm now confused about the ESA's claim to be the "first", because
  I think you might have misread the title, "Europe’s first [...]"
  > Is there a more technical article describing this hyperspectral instrument somewhere?
  https://space.oscar.wmo.int/instruments/view/irs has an short overview
  Then this document provides an introduction (+ details) about the MTG-IRS program in general: https://user.eumetsat.int/s3/eup-strapi-media/MTG_IRS_L2_ATB...

  By diggan 13 hours ago

• > "I think you might have misread the title,"
  No; I'm quoting the esa.int article verbatim. The eumetsat.int article qualifies "...over Europe", but the esa.int does not. I suspect esa.int is just mistaken.

  By perihelions 13 hours ago

• Clearly, if it’s not European, it doesn’t count.

  By dylan604 11 hours ago

• Here is a link that lists the sensors/data products roughly: https://webapps.itc.utwente.nl/sensor/getsat.aspx?Find=sat&N...
  The IRS seems 4km and sentinel 4 8km if I read it correctly. The cool thing is that it is stationary unlike other sentinel satellites and can actually be used for now casting. No clue how infrared sounding performs with cloud cover.

  By riedel 13 hours ago

• [deleted]

  By 13 hours ago

• Imagine a world where America actually wanted to understand climate change.

  By cyanydeez 13 hours ago

• Considering the emissions of the US and the outright rejection of climate action through the Paris accords, and the covering up of climate related research, it would seem fair to consider climate change as partly caused by outright American hostility. They say the most impacted will be people in developing nations, also, not in the US. Absolutely horrific actions.

  By AlecSchueler 11 hours ago

• I think this is the first time I have seen the .int tld used.

  By ArneVogel 14 hours ago

• It isn't super popular, no. I think the requirements are pretty strict if I remember correctly (edit: https://www.iana.org/domains/int/policy).
  I think esa.int is probably one of the more popular .int domains on HN: https://news.ycombinator.com/from?site=esa.int

  By diggan 14 hours ago

• In meteorology, you also have ecmwf.int (the European Center for Medium-Range Weather Forecasts).

  By complex_pi 10 hours ago

• Other notable .int domains:
  • World Health Organization - https://who.int
  • NATO - https://nato.int
  • Council of Europe - https://coe.int
  • Mercosur - https://mercosur.int
  • African Union - https://au.int
  • EFTA - https://efta.int

  By lutoma 11 hours ago

• How long until an executive order is issued to block the .int TLD. Everything on that list goes against current US policies.

  By dylan604 10 hours ago

• interpol.int also comes to mind.

  By r721 13 hours ago

• It would have been better if the requirements also included the domain name had to start with a letter between I and N (inclusive).
  But I guess this is what you get when these things get away from technologists.

  By readthenotes1 13 hours ago

• Ah, a Fortran joke. That's not just "technologists". That's old farts.
  (In Fortran 66, variables didn't have to be declared. They would be integer if they began with I, J, K, L, M, or N. Otherwise it would be floating point [REAL, in Fortran parlance]. To this day it's why for loops usually use "i". With the bonus joke that God is real unless declared integer.)

  By jfengel 13 hours ago

• Maths is the reason for loops use i. Fortran defines variables starting with those letters to be integers because maths has used those letters for iteration, counting, indexing, etc. for centuries. It was natural for a formula translating system to follow suit.

  By mkl 6 hours ago

• I think that's still the case, even in the latest FORTRAN standard. It's usually considered good practice to turn it off with IMPLICIT NONE.

  By spauldo 6 hours ago

• Naive question: what’s the benefit here to scan downward (from the satellite position) over upward, from the ground?

  By aziaziazi 10 hours ago

• If the question is about satellite vs ground instrument: the geographic coverage from the satellite is much greater. Geostationary instruments over Europe cover the Atlantic Ocean, Europe, Africa, the Middle East.
  If that was not the question, can you provide more detail?

  By complex_pi 10 hours ago

• Thanks, this is indeed the question. Thinking out loud: the coverage is probably somewhat conic therefore if you want to scan the ground or lower atmosphere an high altitude is optimal, while scanning the upper atmosphere could be done from the ground.
  Perhaps earth's spherical shape gives an advantage to the satellites in both cases ?

  By aziaziazi 7 hours ago

• Maybe, though a GEO satellite (or really any satellite) will always be much much farther from even the upper atmosphere than the ground will be, so satellites have a pretty dominant coverage advantage.

  By pdabbadabba 6 hours ago

• You can’t drive your sensor bank everywhere on the surface of the earth to point up.

  By mensetmanusman 8 hours ago

• Canada should be next.

  By st3fan 12 hours ago

• Do you have more context? Naively, one would assume the geostationary satellites the US already has in orbit can see Canada just fine.

  By pbmonster 8 hours ago

• access is however, gated behind the american government, and relying on american satelites is a national security risk to canada.
  for example, the US has stopped sharing weather data with canada.

  By 8note 5 hours ago

• > for example, the US has stopped sharing weather data with canada.
  Citation needed. Most weather data from NWS is required by treaty to be disseminated through WMO compliant methods. The Metsat data is transmitted unencrypted from the GOES sats. I don’t believe they even have the capability to encrypt it. It’s only DoD weather data that’s not being widely disseminated, AFAIK.

  By chipsa 4 hours ago

• The Trump administration in February temporarily ordered NOAA to stop communicating with foreign nationals, which included Canadians and included sharing data.
  I don't know if that is still in effect. Google "Did the US stop sharing weather data with Canada?" or ask your favorite LLM that provides references for its answers for more information.

  By tzs 3 hours ago

• Google says: no, the US did not stop sharing weather data. Communication isn’t automated weather data sharing. The data never stopped. Again, citation needed.

  By chipsa 2 hours ago

• [dead]

  By EverydayBalloon 9 hours ago