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

blog.forecast.io

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

#11

Post by thegrossman »

graupel wrote: post #5

I am proud of forecast.io for sticking with a 'normal' color palette here, rather than the non-standard purples they have chosen for radar; as a meteorologist the purple radar hurts my brain, but this map is completely cool. Also there are definitely some quality control issues with the RTMA data, so you can bump into the garbage-in-garbage-out issue with it, but overall, this is a very nice start to something that c…

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.

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

#12

Post by ars »

This isn't a map. This is a simulation. You made a simulation, and are outputting the results.

This teaches you nothing whatsoever except that your model has pretty colors.

Next thing someone is going to take these results, use them as input data for a new model, then send the results of that new model back as data for the first.

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

#13

Post by mturmon »

thegrossman wrote: post #10
mturmon wrote: post #7

Hmm, there are some superlatives ("highest resolution") in here I'm not sure about. Lots of groups create maps like this for modeling purposes. One for sea surface temperature is: http://ourocean.jpl.nasa.gov/SST/ This is a blended product (i.e., multi-instrument, and gaps filled) with 1km resolution. There is also a 1km MODIS land surface temperature data product: http://modis.gsfc.nasa.gov/data/dataprod/dataproduct…

"Real-time" is the key. As far as we know, there isn't another real-time global data product that is this high resolution. And while we actually use MODIS data as an input to our temperature correction model, it is, as you mentioned, land surface temperature, whereas our map represents near-surface air temperature (i.e., what you'd get in a normal weather report).

Good point about "near-surface air temperature".

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

#14

Post by greendestiny »

thegrossman wrote: post #8
deletes wrote: 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!

The legend doesn't update properly, so it really is broken.

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

#15

Post by wahsd »

I wonder if they are aware of the super high resolution weather satellites that NOAA is putting up into orbit and will come on line, I believe, end of this year. I was talking to a high level NOAA official on the technical side and he was saying that it will essentially provide a remarkable, i.e., revolutionary increase in prediction accuracy and be able to provide on the ground climate level predictions.

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

#17

Post by zeckalpha »

wahsd wrote: post #15

I wonder if they are aware of the super high resolution weather satellites that NOAA is putting up into orbit and will come on line, I believe, end of this year. I was talking to a high level NOAA official on the technical side and he was saying that it will essentially provide a remarkable, i.e., revolutionary increase in prediction accuracy and be able to provide on the ground climate level predictions.

I believe most of what they do is aggregation, including of NOAA's data, so this may just improve forecast.io.

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

#18

Post by nkurz »

thegrossman wrote: post #11
graupel wrote: post #5

I am proud of forecast.io for sticking with a 'normal' color palette here, rather than the non-standard purples they have chosen for radar; as a meteorologist the purple radar hurts my brain, but this map is completely cool. Also there are definitely some quality control issues with the RTMA data, so you can bump into the garbage-in-garbage-out issue with it, but overall, this is a very nice start to something that c…

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 sure how refitting the data to ground stations would produce a better match anywhere except at those ground stations (overfitting). Or are you using ground stations that are truly independent?

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

#19

Post by [deleted] »

graupel wrote: post #5

I am proud of forecast.io for sticking with a 'normal' color palette here, rather than the non-standard purples they have chosen for radar; as a meteorologist the purple radar hurts my brain, but this map is completely cool. Also there are definitely some quality control issues with the RTMA data, so you can bump into the garbage-in-garbage-out issue with it, but overall, this is a very nice start to something that c…

[deleted]

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

#20

Post by nkurz »

ars wrote: post #12

This isn't a map. This is a simulation. You made a simulation, and are outputting the results. This teaches you nothing whatsoever except that your model has pretty colors. Next thing someone is going to take these results, use them as input data for a new model, then send the results of that new model back as data for the first.

This isn't a map.

What would a better map be? Is your point that they are doing interpolation on something that is already interpolated? Or are you implying that there is no way to create a map of temperature using only point measurements? I would like to know how well this data matches the raw station measurements (and verification measurements) but I think it's a decent visualization of likely real time temperature across a region.

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