Folks
As a Dutch weatheramateur I publish a daily infra red cloudcover map from the geostationary weathersatellites. I have created now a version for Celestia showing you the earth (except the earth poles, they are covered by the satellites) in false colors from the IR-channel. I hope that the motherlode will accept this ir-maps, but you can download the demo with all info needed from:
http://www.meteo-maarssen.8m.com/data/celestia/misc/earth-ir1K.zip
A sample:
http://www.meteo-maarssen.8m.com/data/celestia/earth-ir041030.jpg (around 220 kB)
Images are published every day between 18/22 UTC and shows you the earth in IR from 12 UTC.
Cheers,
Ton Lindemann
Earth in IR, every day refreshed!
-
Ton Lindemann
- Posts: 19
- Joined: 29.10.2004
- With us: 20 years
- Location: Maarssen, Netherlands
Hi,
What you actualy see is a temperature map of the earth for a given time. On the raw images/data cold is represented as white and heat is black. Thus the cold cloudtops appears as white and the heat of the deserts as black. The satellite is measuring the radiation from the surfaces he can see. It can't look through the clouds, so most of the time the white pixels are could cloudtops. But not always. During wintertime over Canada, Northern Scandinavia ans Siberia my look full overcast by clouds. The cause is most of the time very low temperatures over snow or icecover and it will look as upper level high clouds in the sky, because of its very low temperatures. Clouds can't be discriminated from snow, ice or very cold air at the surface in the IR channels. On the other hand over the tropics relative warm clouds (near surface clouds) are hard to see. They are melting/fading in the radiationheat of the tropical sea's, deserts and forests.
What we are seeing is most of the time clouds. The high level cloudtops are used to find front locations (most of time bands of clouds) and thin cirrus. The large ovals in a bands over the tropics are tropical thunderstorms. Low level cloudtops can be used to find locations of fog, stratus and small cummuliform clouds. And very important: We do have an overview of clouds during during the night, where visual images are not very useful.
The used technic for this offered dataset is to remap the full disk images for all the five satellites to a format Celestia can read. Then each pixel on the grey-scale from the IR image is representing a specific temperature. Each grey scale pixel can be recolored in another. This technic is used for the Celestia IR versions and I use the same model for my daily weathermaps. I use the IR images and superimpose the weathermaps on it. Feel free to take a look at my pages and you will see the match of high's and lows with the clouds, but beware; I'm serving the Dutch marked and all is in Dutch. Scroll down to <wereld weer atlas = world weather atlas>. Dutch names for continents and oceans are almost the same as in English, so you will find the way here. This is the best way to show you how we can use the satellite images.
http://www.meteo-maarssen.8m.com/achtergrond/satelliet/satellietfoto.htm
I'm now trying to use the IR images as a kind of speudo visual cloudmap over an earth surfacemap. There are limits: I'm not able to create cloudmaps in layers, but the benefit is that you have a natural look and and IR-look alike for same time, almost each day of the year.
A preview (not operational) is available at:
http://www.meteo-maarssen.8m.com/data/celestia/earth-cl041030.jpg
If you are interest in this stuf, then visit the homepage of David Taylor (Scotland). He is offering all kind of software for use of almost all weathersatellites. His homepage:
http://www.satsignal.net
Look for GeoSatSignal for geostationary satellites as GOES and Meteosat and for SatSignal for the polar orbiters as NOAA. Both programs can handle data from direct satellite readout as from internet sources as well. This is not freeware, but shareware.
Hope this helps,
Cheers,
Ton Lindemann
What you actualy see is a temperature map of the earth for a given time. On the raw images/data cold is represented as white and heat is black. Thus the cold cloudtops appears as white and the heat of the deserts as black. The satellite is measuring the radiation from the surfaces he can see. It can't look through the clouds, so most of the time the white pixels are could cloudtops. But not always. During wintertime over Canada, Northern Scandinavia ans Siberia my look full overcast by clouds. The cause is most of the time very low temperatures over snow or icecover and it will look as upper level high clouds in the sky, because of its very low temperatures. Clouds can't be discriminated from snow, ice or very cold air at the surface in the IR channels. On the other hand over the tropics relative warm clouds (near surface clouds) are hard to see. They are melting/fading in the radiationheat of the tropical sea's, deserts and forests.
What we are seeing is most of the time clouds. The high level cloudtops are used to find front locations (most of time bands of clouds) and thin cirrus. The large ovals in a bands over the tropics are tropical thunderstorms. Low level cloudtops can be used to find locations of fog, stratus and small cummuliform clouds. And very important: We do have an overview of clouds during during the night, where visual images are not very useful.
The used technic for this offered dataset is to remap the full disk images for all the five satellites to a format Celestia can read. Then each pixel on the grey-scale from the IR image is representing a specific temperature. Each grey scale pixel can be recolored in another. This technic is used for the Celestia IR versions and I use the same model for my daily weathermaps. I use the IR images and superimpose the weathermaps on it. Feel free to take a look at my pages and you will see the match of high's and lows with the clouds, but beware; I'm serving the Dutch marked and all is in Dutch. Scroll down to <wereld weer atlas = world weather atlas>. Dutch names for continents and oceans are almost the same as in English, so you will find the way here. This is the best way to show you how we can use the satellite images.
http://www.meteo-maarssen.8m.com/achtergrond/satelliet/satellietfoto.htm
I'm now trying to use the IR images as a kind of speudo visual cloudmap over an earth surfacemap. There are limits: I'm not able to create cloudmaps in layers, but the benefit is that you have a natural look and and IR-look alike for same time, almost each day of the year.
A preview (not operational) is available at:
http://www.meteo-maarssen.8m.com/data/celestia/earth-cl041030.jpg
If you are interest in this stuf, then visit the homepage of David Taylor (Scotland). He is offering all kind of software for use of almost all weathersatellites. His homepage:
http://www.satsignal.net
Look for GeoSatSignal for geostationary satellites as GOES and Meteosat and for SatSignal for the polar orbiters as NOAA. Both programs can handle data from direct satellite readout as from internet sources as well. This is not freeware, but shareware.
Hope this helps,
Cheers,
Ton Lindemann
I've just noticed by looking at these cloud maps that all the cloud movement is probably cause by friction of some kind against space.
From this 2D point of view, across the centre is where earth is moving from left to right which makes the clouds drag the way they do.
I wonder if we took a clear sphere shaped object, filled it with some kind of smoke then put a slightly smaller one inside that and span it anti-clockwise. I bet the same cloud formations would appear. But maybe this is already common knowledge.
From this 2D point of view, across the centre is where earth is moving from left to right which makes the clouds drag the way they do.
I wonder if we took a clear sphere shaped object, filled it with some kind of smoke then put a slightly smaller one inside that and span it anti-clockwise. I bet the same cloud formations would appear. But maybe this is already common knowledge.
-
Ton Lindemann
- Posts: 19
- Joined: 29.10.2004
- With us: 20 years
- Location: Maarssen, Netherlands
Seb,
This is a good conclusion. In general airmasses, or maybe better weathersystems as high's and low's are moving east on earth at mid latitudes. But moving west near the equator (look at e.g. hurricans:
traffeling from Africa to the Carribean and there via North America to the northern Atlantic/Europe. Remnants of them can be the cause of heavy precipitation and thunderstorms in Europe.
The mid latitudes are the origin of depressions, because warm and cold air meets there and have a battle; the cause of fronts (spiral form of clouds).
By the way: Did you know that <front> in the meteorology was addapted from the World War I, where <front> was introduced by the generals and soldiers fighting in Belgium? The front/cyclone theory has almost the same age!
Cheers,
Ton Lindemann
This is a good conclusion. In general airmasses, or maybe better weathersystems as high's and low's are moving east on earth at mid latitudes. But moving west near the equator (look at e.g. hurricans:
traffeling from Africa to the Carribean and there via North America to the northern Atlantic/Europe. Remnants of them can be the cause of heavy precipitation and thunderstorms in Europe.
The mid latitudes are the origin of depressions, because warm and cold air meets there and have a battle; the cause of fronts (spiral form of clouds).
By the way: Did you know that <front> in the meteorology was addapted from the World War I, where <front> was introduced by the generals and soldiers fighting in Belgium? The front/cyclone theory has almost the same age!
Cheers,
Ton Lindemann
-
Ton Lindemann
- Posts: 19
- Joined: 29.10.2004
- With us: 20 years
- Location: Maarssen, Netherlands
Folks,
The earth speudo-visual (simmulated visual) is available now, but only once a day as with the earth-ir and only for 12 UTC. Filename convention identical as the infrared version;
earth-cl[yymmdd].jpg, thus
earth-cl041112.jpg
URL: http://www.meteo-maarssen.8m.com/data/c ... 041112.jpg
Both versions will be upgraded to 4k soon as possible.
Cheers,
Ton Lindemann
The earth speudo-visual (simmulated visual) is available now, but only once a day as with the earth-ir and only for 12 UTC. Filename convention identical as the infrared version;
earth-cl[yymmdd].jpg, thus
earth-cl041112.jpg
URL: http://www.meteo-maarssen.8m.com/data/c ... 041112.jpg
Both versions will be upgraded to 4k soon as possible.
Cheers,
Ton Lindemann
-
Ton Lindemann
- Posts: 19
- Joined: 29.10.2004
- With us: 20 years
- Location: Maarssen, Netherlands
-
Ton Lindemann
- Posts: 19
- Joined: 29.10.2004
- With us: 20 years
- Location: Maarssen, Netherlands
Folks,
The Celestia world weather satellite textures are moving to a new folder on march 1, 2005:
The new URL will be:
http://www.meteo-maarssen.8m.com/data/textures
cheers,
Ton Lindemann
Netherlands
BTW: Is there any interest in having a daily (00 UTC) sea level pressure map for use in Celestia?
The Celestia world weather satellite textures are moving to a new folder on march 1, 2005:
The new URL will be:
http://www.meteo-maarssen.8m.com/data/textures
cheers,
Ton Lindemann
Netherlands
BTW: Is there any interest in having a daily (00 UTC) sea level pressure map for use in Celestia?