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An attempt to create the highest resolution real-time map of global temperature

blog.forecast.io

21–30 of 42 posts

Re: An attempt to create the highest resolution real-time map of global temperature

#21
Just for the fun of it, for those of you in the bay area, here's a surface temperature forecast for today, 16:00 PST. It is from the forecast site that I've been maintaining for some time now - http://www.norcalsoaring.org/BLIP/BYRON/index.html

http://raspbucket.s3-website-us-west-2.amazonaws.com/BYRON/F...

(Based on 3km/750m WRF model run two times a day based on the NCEP data. )

Re: An attempt to create the highest resolution real-time map of global temperature

#22
Nice work!

There seems to be a typo in the Stats (my emphasis):

>Pixels: 16-bit unsigned ints, representing "deci-kelvin" (i.e., divide by 100 to get the temperature in Kelvin).

It should either be centikelvin or divide by 10.

On another note: It would be cool if you could hover over a certain area to see its temperature.

Re: An attempt to create the highest resolution real-time map of global temperature

#25

Nice work! There seems to be a typo in the Stats (my emphasis): >Pixels: 16-bit unsigned ints, representing " deci -kelvin" (i.e., divide by 100 to get the temperature in Kelvin). It should either be centikelvin or divide by 10. On another note: It would be cool if you could hover over a certain area to see its temperature.

Oops, it should read centikelvin. Fixed! Thanks.

Re: An attempt to create the highest resolution real-time map of global temperature

#26
post #18

Earlier quoted context omitted.

Also: Validation is tricky, since we can't just compare the output to ground station observations, as we incorporate ground station data into the model. Eventually I want to generate alternative versions that randomly exclude specific stations so we can use them for comparison.

I think RTMA already includes ground station measurements, so analyzing performance using a leave-N-out strategy wouldn't be a good verification: http://nomads.ncep.noaa.gov/txt_descriptions/RTMA_doc.shtml http://eamcweb4.usfs.msu.edu/mm5-case/RAWS/RTMA%20papers/pon... Instead, I think you'd need to find temperature measurements that are completely independent and use them for verification. Along this line, I'm not s…

When we compare it to RTMA, we leave out RTMA from the list of data sources. Likewise, eventually I'd like to do the same with a subset of the ground stations we use.

(The problem with finding completely independent measurements is that we'd want to use them as an input!)

Re: An attempt to create the highest resolution real-time map of global temperature

#27

It's a cool project, but... >>It regenerates every hour, providing a constantly updating snapshot of air temperature around the globe. Once per hour is not "real-time." It's "once per hour."

Having done a lot of real-time programming myself, it's really in the eye of the beholder. And there are snobs who think that nothing less than several kilohertz is real-time.

But historically, "real-time" means "not batch mode" - where batch jobs are executed whenever there are available resources, in an unpredictable manner.

Real-time is responding to real world input on some periodic schedule that is appropriate. In this case, one hour sounds fine for a world temperature map. Are you expecting to make minute-to-minute decisions based on the global temperature distribution?

Local temperature I'd expect to be updated faster, but really it's a matter of your use-case.

Re: An attempt to create the highest resolution real-time map of global temperature

#29
post #3

This is pretty impressive, i wonder what the update interval and source is. http://www.mapbox.com/labs/forecast/temperature/ I really like the interface, even the zoom buttons could be removed or hidden as you can scrool-zoom. Make the temperature in Celsius please! EDIT: There seem to be a problem with the algorithms, the largest zoom displays colder temperatures( look at the temperature map ). Largest zoom, http://…

The color palette adjusts based on the zoom level in order to improve contrast. Roughly a bazillion people pointed out that it's "broken", so I guess that was a dumb call on my part!

Shouldn't it adjust based on the extremes (Or standard deviation) within the zoom area? In that case there would always be some purple, and should fix at least the specific problem the parent showed.

Re: An attempt to create the highest resolution real-time map of global temperature

#30
post #2

Celsius please. But besides that: Very nice, very clear and way better than supid sun and cloud icons with temperatures next to them over some vague areas.

Absolutely.

Only about 320 million [1] out of 7 billion people still use fahrenheit.

[1] http://en.wikipedia.org/wiki/Fahrenheit#Usage

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