The Climate is Beautiful.

THE CLIMATE IS BEAUTIFUL

One of the links in the blog roll is not a blog.
The Earth weather viewer {link}
If your browser or web connection does not support this site or is too slow, upgrade, you are missing out on a fundamental aspect of how knowledge can be made accessible in the Information Age. Check it works for you and read on….

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http://earth.nullschool.net/

This is a wonderful bit of software that generates an animated picture of wind speeds at various altitudes while also showing a selection of other parameters like temperature pressure and humidity. Click on the word EARTH at the bottom left to get at the menu of extensive options. Most have an explanation if you hover over them with the mouse. Now there is surpassing cleverness in taking the realtime weather station and satellite data and feeding it into a computer model,- yes is is using modelling to interpolate the data – to give a record, realtime and future prediction of wind speed and weather conditions at any point or altitude on the globe.

That is a pretty awesome bit of programming and data analysis. I don’t really care how accurate it is, the mere ability to attempt something like that and get a credible result is a demonstration of the high level of understanding that has developed in the climate field.

But there is more to it than that.
I first saw the effect used on the site, still up {link} but possibly not active, that produced an animated map of North American wind speed and direction. As mentioned on that site it was as much an art project as scientific, an exercise in data visualisation.
The techniques of portraying movement or flow as fading trails of points is not new. The human visual system interprets directional blur on an image as movement, leaving a trail behind a moving point has been a means of portraying direction and speed in other areas from Disney cartoons to air traffic control systems.

But the specific method here is to start a data point and move it according to the wind speed measured or calculated at that point and set a speed of fade for the point. The result is that slow moving points have short tails, fast points long fading tails generating the visual impression of differential speed much more strongly than just the moving point could do.
However as anyone who has played around with animation will know the precise timing and intensity of the fade is critical to produce a convincing effect. Too little and there is a failure to amplify the perception of speed, too much and the background is rapidly overlaid by a skein of confusing intersecting lines.

The site depicting US winds is strictly monochrome. I am certain that much programming cleverness went into getting the trail fade effect just right to convey the speed and direction most strongly. That is an achievement in itself. But a surprisingly short time later the Earthschool.null site appeared, and here it employs not only the fade trail effect seen on the earlier site, but incorporates color, both for wind intensity and other surface and atmospheric measures. Very rarely do the color palettes clash or lead to ambiguity. That elegant manipulation of the color and brightness palette is another rather impressive achievement, especially to anyone who has struggled to avoid colour clash and pastel bleaching!

The default display at the site is of a rendered 3D globe, the wind trails mapped over the spherical surface. However the maths to do that, convert the gridded data into a spherical map is closely allied to the maths that maps a spherical surface onto a flat plane. These have been included as options in the display. So you can select a display of the spherical surface of the whole globe as a 2D projection in various forms. In all these display forms mouse dragging moves your POV, or the way the globe is mapped onto the flat plane, and mouse wheel zooms in and out. Try the Azimuthal Equidistance with the N pole in the centre and the S pole as the outer edge for a terrestrial version of DiscWorld! {Link}

The sheer cleverness of the programming to get a global gridded dataset for wind speed and various altitudes and the other parameters mapped onto a globe is impressive enough, but as you probably gather, this blogger who dabbles in animation finds the artistic optimisation of the fading trail effect, in colours, just as admirable.

The result is a site which is of some practical use. The data is not finely resolved enough perhaps for local weather but as a means of seeing the bigger picture and what’s coming in a day or two it is unsurpassed. The 850 to 250 pressure levels reference an altitude of a kilometre on up or so and can give a view of the jets streams or major storms developing before they impact the surface.

Here is a rough animation of static screens of the weather on the US East coast Jan27th 2015, the snow storm that skipped NY.WEATHER_3

But beyond that is the fact it is very very beautiful. Set it up with a view of an active weather region, in any form of display that shows it well, and leave it as an animated wallpaper, the slow, ever changing development of the wind speeds at different levels and the temperature and water content of the atmosphere can be followed over time, just for the aesthetic delight in a truly beautiful display of the complex interplay of wind and energy on the surface of our planet.

The climate is VERY beautiful!


Postscript, I have tried to set this webpage up as my screensaver using a bit of freeware that does allow a webpage to be used as the screensaver display. Unfortunately while it works for many sites, for some reason it reports a need for a browser upgrade when it accesses this site although the browser works and displays it correctly when accessed direct.
If anyone knows of any other screensaver software, preferably free, that might display a web page reliably, thanks!

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2 responses to “The Climate is Beautiful.

  1. The wind effects are beguiling, but I’m not sure they are so informative. They look dynamic, but the fields are static. That is, he takes a snapshot of the speeds at a point in time, and moves points in line with that frozen velocity. In fact, in the time the particles moved that distance, the circulations would have changed.

    I actually think the plots would tell more without the wind.

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  2. I take your point that the animated trails are a representation of an instant of a dynamic vector field and portrays the wind speed/direction of a snapshot, not a continuous updated display.

    But that display is updated every three hours, and I would suggest that the difficulties of continuously, in realtime, modifying the flow directions would be hard given the extent of realtime information available.

    It still, despite the limitation you point out, gives a good perceptual impression of the wind speed and direction. I found the written description of the source of the recent US snowstorm on the Jeff Masters blog difficult to follow, with the talk of a jet stream loop at high levels delivering a cold low descending to the surface and a storm vortex forming as a result of the temperature difference, especially between land and sea.

    Being able to follow the wind, temperapture and pressure, as well as precipitation water, at different levels made that description concrete for me in a way the words did not.

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