

An attempt to create the highest resolution real-time map of global temperature - rjsamson
http://blog.forecast.io/project-quicksilver/

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WA
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.

~~~
ra
Absolutely.

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

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

~~~
nevster
It's less than the percentage of the world still using IE6!

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officialjunk
Even if normalized for people that actually have Internet access? Honest
question.

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ArturSoler
The IE6 share is going to be higher when normalized for people with Internet
access, so the comparison is going to hold by a wider margin.

~~~
officialjunk
Doh. You're right. Not sure what I was think at that moment :)

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graupel
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 could ultimately be quite useful.

~~~
thegrossman
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.

~~~
nkurz
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://nomads.ncep.noaa.gov/txt_descriptions/RTMA_doc.shtml)
[http://eamcweb4.usfs.msu.edu/mm5-case/RAWS/RTMA%20papers/pon...](http://eamcweb4.usfs.msu.edu/mm5-case/RAWS/RTMA%20papers/pondeca_2012_RTMA.pdf)

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?

~~~
thegrossman
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!)

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deletes
This is pretty impressive, i wonder what the update interval and source is.

[http://www.mapbox.com/labs/forecast/temperature/](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://i.imgur.com/GVt3iSy.jpg](http://i.imgur.com/GVt3iSy.jpg)

Normal zoom, picture was resized by me

[http://i.imgur.com/t1GgrOM.jpg](http://i.imgur.com/t1GgrOM.jpg)

~~~
thegrossman
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!

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

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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.

~~~
nkurz
_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.

~~~
ars
> Is your point that they are doing interpolation on something that is already
> interpolated?

Yes.

> but I think it's a decent visualization of likely real time temperature
> across a region.

Maybe I'm being pedantic, but to me this is a 2D visualization of a
simulation. But it is not a map.

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mturmon
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/](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/dataproducts.php?MO...](http://modis.gsfc.nasa.gov/data/dataprod/dataproducts.php?MOD_NUMBER=11)

Neither of these is real-time (more like daily).

~~~
thegrossman
"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).

~~~
mturmon
Good point about "near-surface air temperature".

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dchichkov
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://www.norcalsoaring.org/BLIP/BYRON/index.html)

[http://raspbucket.s3-website-us-
west-2.amazonaws.com/BYRON/F...](http://raspbucket.s3-website-us-
west-2.amazonaws.com/BYRON/FCST/sfctemp.curr.1600lst.d2.png)

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

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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.

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

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coldsmoke
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.

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thegrossman
Oops, it should read centikelvin. Fixed! Thanks.

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sirwitti
Please use Celsius or at least show both.

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mtdewcmu
I don't get where the data is coming from. A lot of it must be interpolated.

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film42
Amazing stuff! It's things like this that makes me proud to be a developer.

This leaves me wondering, how does one go about designing such a system? Are
you planning on doing a technical write up soon?

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mrtimo
I didn't realize how hot eastern china was!

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micah63
Most of China's 3million+ cities are on the east coast, the west is relative
unpopulated. I was there in November and while the results of this map
shouldn't have surprised me, considering the extreme city expansions I saw, I
was still very surprised to see that half the country is at the same level as
Saudi Arabia!

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btbuildem
In lowest zoom level, if you scroll the map, it snaps back to the original
center after scrolling fades out.

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enraged_camel
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."

~~~
Isamu
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.

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tunato
very cool

