Comment by lauri_jo
8 hours ago
This data is from the third generation of Meteosats, which are the European meteorological satellites. A lot like GOES in the north-America. The main improvement is really significant improvement in resolution. The resolution is, depending on the channel, 9 times better than in the second generation. The main improvement in forecasting comes due to better information in the initial condition of the numerical weather prediction, but it is hard to quantify in advance. I'd be surprised if MAE, over the 15 days the prediction spans, would improve more than 0.1 C, if we talk about the raw prediction. There are plenty of things that this data is used for, but I would say that improved nowcast of cloud coverage, and energy production related parameters are likely to benefit most from the improvement in resolution.
They also feature that the IR hyperspectral measurement is new -- 1700 channels in IR for a telescope in GEO seems new to me, but I'm not sure what exists now in this space.
They say they hope to retrieve trace gases at that global scale (seemingly with 30 minute cadence), which I think would be new. Also, they seem to say that this spectral resolution would enable them to retrieve temperature and humidity as a function of height -- not just surface temperature and column-integrated water content ("humidity").
Aha, here's a nice link (https://www.ssec.wisc.edu/geo-ir-sounder/) on exactly this question, pointing out the NASA IR sounders that have existed for many years (AIRS). These instruments get vertically-resolved atmospheric information, but they are not at GEO so their coverage is different. This makes them less useful for NWP.
I use windy.com for its 'compare models', the models can differ by ~2C sometimes
The difference in wind speeds can be quite significant, which greatly alters some forecasts.
The question is often when it will rain, not if it will rain.