31–40 of 105 posts
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It's far too expensive with dubious impacts on forecast quality. Adaptive mesh approaches are far more suitable for high res global weather modeling... Why simulate the area under boring, dynamically unimportant areas?
> Why simulate the area under boring, dynamically unimportant areas? Butterflies... terrifying large, kilometer-scale butterflies.
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You want to know the precise shape of the Earth's surface in femtometer precision? There are some profound problems with that idea once you get below 10 meter or so, but I'll let you think that one through yourself.
No, but I wouldn't mind weather measuments every cubic femtometer of the lower atmosphere and a fast enough computer with enough memory to cruch the data and accurately report what the weather will be like on 29 February.
https://en.wikipedia.org/wiki/Femtometre
I mean you can’t even fit a thermometer into a cubic femtometer..?
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Which is *exactly* why ultra-high resolution global weather simulation has dubious prospects for improving forecasts. When you're at spatial scales where you need to parameterize convection, there's an inherent "smoothness" to model solutions that suppresses noisy errors. If you go to cloud-resolving scales - which is needed for simulations like the ones here - you don't get the benefit of that smoothness anymore, be…
If we're ever going to get to the femtometer resolution required for very precise 100 day weather forecasting, we have to start somewhere, so let them waste their time. It's not as though this is part of a growing trend to abandon conventional weather and climate modeling.
This is for short term weather prediction or long term climate modelling? The 2.5 simulated days per day points into the short term direction.
As mentioned in the article, the system is based on the ICON Earth System model[1], which has the following description: The Earth system model provides a numerical laboratory for research on the climate dynamics on time scales of a season to millennia. Necessarily most processes are parameterized to allow the computationally efficient integration over long periods. It's also mentioned it will contribute to DestinE[2…
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Why do you think that we need "femtometer resolution" for "very precise" 100 day weather forecasting? What even is "very precise" 100 day weather forecasting? I think it's very amusing to do the math on how much memory would be required to run a crude primitive equation dycore over even the tiniest of domains at femtometer resolution :) > It's not as though this is part of a growing trend to abandon conventional weat…
> Why do you think that we need "femtometer resolution" for "very precise" 100 day weather forecasting? Due to sensitive dependence on initial conditons. Even using measurements at meter resolution will cause the accuracy of a forecast to begin to break down after only a few days. > What even is "very precise" 100 day weather forecasting? Anywhere from accurate to exact. > I think it's very amusing to do the math on…
* It's pretty hard to predict weather for 100 days, because you would also need to predict many other events in the future: forest fires, volcano eruptions, and many kinds of human activity that also affect weather. However great are your fluid dynamic models, and however well were they able to predict the future state from today's state, they wont help that.
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> Why do you think that we need "femtometer resolution" for "very precise" 100 day weather forecasting? Due to sensitive dependence on initial conditons. Even using measurements at meter resolution will cause the accuracy of a forecast to begin to break down after only a few days. > What even is "very precise" 100 day weather forecasting? Anywhere from accurate to exact. > I think it's very amusing to do the math on…
* You don't have the density of sensors to see even at a meter resolution, to say nothing of femtometer. Actually in oceans you don't have many sensors at all, and most data come from satellite observations that give rather indirect information. Even if you had a capability to compute a model at femtometer resolution, I don't see how much of it would you be able to fit to observations. * It's pretty hard to predict w…
At the moment, no. But maybe there will be a way to accurately sense weather data at any location from LEO. IR thermometers are pretty neat, maybe something metaphorically along those lines, a satellite with a laser technology that could beam back accurate weather data from any location, and all atmospheric locations it can see along its orbit, sending the data to ground-based ultra-computer networks running simulations.
In 1933, no one would have believed that GPS was 40 years away. In 1985 most would not have been able to understand how flat and thin color monitors were only a decade away, nor that mRNA vaccines were less that 30 years away. Similarly, we really don't know what the future of weather sensing and prediction will be like in 2070, and if we could know, we wouldn't understand how it would be possible.
Eg how do hou predict the temperature at x,y? Is it ground type, water, sand?Altitude? Neighboring values thereof?
What are the inputs? Do you give it a starting point and apply it to a bunch of elements like some giant automata like game of life?
Some kind of finite element analysis thing?
So many questions.