It turns out that yes, better forecasts is a large part of what motivated the launch of this instrument.
High-spectral-resolution IR spectra at GEO allow estimation of vertically-resolved temperature and water vapor (over large spatial areas, at high temporal cadence), which are then assimilated. Forecasts and nowcasts thus improve.
These "spectra-to-get-temperature-and-water" measurements were pioneered by other instruments in LEO (e.g., NASA's AIRS, https://airs.jpl.nasa.gov/mission/overview/), but LEO does not provide enough coverage to help forecasts.
To understand the benefits of GEO IR spectra, we do "OSSE's" (Observing System Simulation Experiments) to quantify how much improvement you get. You take a "Nature Run", make simulated observations (existing and proposed), and see if there is an improvement. (Since the Nature Run, which you made, provided ground truth, you can judge if there really was an improvement.)
In particular, looking at the figure there from Li et al., compare panels:
* (d) -- (Nature Run) - (existing data) ("CNTRL")
* (e) -- (Nature Run) - (existing data + GEO IR)
which both show differences between the Nature Run (NR) and the forecast.
The RMSE improvement (on a CONUS storm) is given as RMS of 0.55 (existing) versus 0.43 (with GEO IR), in degrees Kelvin. So that's 0.12 Kelvin or 0.22 Fahrenheit. Also, and probably more interestingly, the spatial pattern changes.
Studies like this (i.e., OSSEs like the ones above) are one of the main ways we decide how to build the next instruments -- what provides the most benefits vs. cost, which system parameters to push to improve and which are good enough.
I recently met a European space startup founder and was surprised to learn how much space innovation is happening in Europe with ESA. Europe wants to become less depended on SpaceX and NASA, and is heavily investing there. More funding + strong aerospace programs at universities like TU Munich has led to companies like ISAR Aerospace (SpaceX competitor), which is great to see.
Unlikely. EU countries are consistently restrictive about access to this kind of data. Even when it is available, it often has odd restrictive licensing. This is an area where the US, with its liberal data access policies, is far ahead of Europe.
Something else to keep in mind is that the data products are extremely large. It would be expensive to give the public access. I used to host these types of data sets for EU countries. The workload just from authorized users is resource intensive, it doesn't scale cheaply. (I once woke up to find a metaphorical smoking crater where my server racks were because an authorized user shared his credentials with a few friends overnight.)
EU citizens can get free access to it via Eumetcast DVB-S service for non-commercial use. A registration, an off-the-shelf DVB-S data receiver, a satellite dish and their decryption USB key is required. FOSS software like Satpy is available for processing those radiometric data. More info: https://user.eumetsat.int/resources/user-guides/eumet-cast-e...
I hate to worry everyone, but I think there might be some triangular chunks missing off the corners of our planet, someone should probably look into this.
(Specifically around 2, 5, and 10 o clock on the orientation of the images provided)
Picking it up is no problem for some specialists in the (ham) radio scene. They are mastering X- and S-band stuff so good that even the NASA asked them to join in some observations in the past.
But: Meteosat is very famous for encrypting their stuff.
I have not done it once (work in programming for 40+ years) as independent. Few times potential clients tried to play this game but I just simple refuse. On was surprised and asked why? My answer was - I have a track record of successful deliveries, here is big list of projects, emails and phone numbers to confirm. If you are going instead to rely on some tests to prove my abilities I have better things to do then be a schoolboy on exams.
Europe is widely acknowledged as having arguably the best global weather systems. This isn't new. There are only a handful of organizations world-wide maintaining global weather models.
The US government, uniquely, maintains two independent global weather models. Neither is as good as the European model. Arguments have been made for combining the US budgets to produce a best-in-class weather model but politics makes that unlikely to happen.
ESA has done a lot of good for public benefit with the Sentinel-1/2 missions. I happen to work with remote sensing and Sentinel data has been my entry point to the field.
I hope that ESA keeps pushing forward even more. I am afraid that although Sentinel missions are great, ESA projects are a bit demo-like and limited in scope. Europe should focus on scaling up and applying the tech, not just proving that ambitious projects are possible for their own sake.
> ESA projects are a bit demo-like and limited in scope
I am kind of confused by that statement, what more would you expect from the Copernicus Programme? Isn't it a technical improvements over NASA's LANDSAT programme?
I don't mean "demo-like" in terms of poor technology. I meant that this technology doesn't yield products or services with global scales to an extent it happens in the US. Google Maps successfully uses both LANDSAT and Sentinel imagery. This is the wider problem of European failure to build companies/systems on top of technology.
Congrats ESA! Those first images are pretty striking. It's pretty cool to see the contrast between the blue high altitude clouds and the red hot surface, particularly just below the Sahara.
Is there any info about the modulation/encoding/frequency?
It would be great to have an open source decoder for RTL-SDR like we have for NOAA or METEOR.
The most surprising thing on this page for me was:
> The areas of least atmospheric humidity ... a large area of ‘dry’ atmosphere also covers part of the South Atlantic Ocean (centre of image).
This area is not that far south as to basically indicate the antarctic, and it is warm season in the southern hemisphere. I did not even think it would be possible to have a larger area of low humidity over a massive ocean like that.
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[ 2.9 ms ] story [ 62.1 ms ] threadIt turns out that yes, better forecasts is a large part of what motivated the launch of this instrument.
High-spectral-resolution IR spectra at GEO allow estimation of vertically-resolved temperature and water vapor (over large spatial areas, at high temporal cadence), which are then assimilated. Forecasts and nowcasts thus improve.
These "spectra-to-get-temperature-and-water" measurements were pioneered by other instruments in LEO (e.g., NASA's AIRS, https://airs.jpl.nasa.gov/mission/overview/), but LEO does not provide enough coverage to help forecasts.
To understand the benefits of GEO IR spectra, we do "OSSE's" (Observing System Simulation Experiments) to quantify how much improvement you get. You take a "Nature Run", make simulated observations (existing and proposed), and see if there is an improvement. (Since the Nature Run, which you made, provided ground truth, you can judge if there really was an improvement.)
Thankfully, many people have already done this. See: https://www.ssec.wisc.edu/geo-ir-sounder/osse/
In particular, looking at the figure there from Li et al., compare panels:
* (d) -- (Nature Run) - (existing data) ("CNTRL")
* (e) -- (Nature Run) - (existing data + GEO IR)
which both show differences between the Nature Run (NR) and the forecast.
The RMSE improvement (on a CONUS storm) is given as RMS of 0.55 (existing) versus 0.43 (with GEO IR), in degrees Kelvin. So that's 0.12 Kelvin or 0.22 Fahrenheit. Also, and probably more interestingly, the spatial pattern changes.
There are a lot of OSSE's reported on that page for these sounders. NASA is also conducting OSSE studies for a more ambitious multi-spacecraft observing system (https://science.nasa.gov/earth-science/decadal-surveys/decad...).
Studies like this (i.e., OSSEs like the ones above) are one of the main ways we decide how to build the next instruments -- what provides the most benefits vs. cost, which system parameters to push to improve and which are good enough.
Something else to keep in mind is that the data products are extremely large. It would be expensive to give the public access. I used to host these types of data sets for EU countries. The workload just from authorized users is resource intensive, it doesn't scale cheaply. (I once woke up to find a metaphorical smoking crater where my server racks were because an authorized user shared his credentials with a few friends overnight.)
https://user.eumetsat.int/resources/user-guides/data-registr...
Look for your dataset here https://data.eumetsat.int/ (Note: you need registration but it is free).
https://www.eumetsat.int/features/see-earths-atmosphere-neve...
(Specifically around 2, 5, and 10 o clock on the orientation of the images provided)
But: Meteosat is very famous for encrypting their stuff.
I have not done it once (work in programming for 40+ years) as independent. Few times potential clients tried to play this game but I just simple refuse. On was surprised and asked why? My answer was - I have a track record of successful deliveries, here is big list of projects, emails and phone numbers to confirm. If you are going instead to rely on some tests to prove my abilities I have better things to do then be a schoolboy on exams.
Their stuff basically works 24/7/365 without causing much noise. With fully automated data intake processes.
The US government, uniquely, maintains two independent global weather models. Neither is as good as the European model. Arguments have been made for combining the US budgets to produce a best-in-class weather model but politics makes that unlikely to happen.
Try a different app. Some let you choose from a list of different weather sources.
I hope that ESA keeps pushing forward even more. I am afraid that although Sentinel missions are great, ESA projects are a bit demo-like and limited in scope. Europe should focus on scaling up and applying the tech, not just proving that ambitious projects are possible for their own sake.
Check out their video on what kind of data it unlocks if you have five minutes and want to get your mind blown. https://youtube.com/watch?v=rXCBFlIpvfQ
I am kind of confused by that statement, what more would you expect from the Copernicus Programme? Isn't it a technical improvements over NASA's LANDSAT programme?
> The areas of least atmospheric humidity ... a large area of ‘dry’ atmosphere also covers part of the South Atlantic Ocean (centre of image).
This area is not that far south as to basically indicate the antarctic, and it is warm season in the southern hemisphere. I did not even think it would be possible to have a larger area of low humidity over a massive ocean like that.