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Climate Anomaly on the Sahara

Continuing to monitor the interesting changes taking place on the Sahara desert this year.
Below is a link to a previous article posted here which contains two animated gifs of the rain patterns on the Sahara in August and September, 2015.

homepage: homepage: http://portland.indymedia.org/en/2015/10/430799.shtml


500 mb wind vectors 12.Nov.2015 11:14

Brent

In the graphic above you can see the 500 millibar winds for Thursday, November 12th, You can see how the winds are dipping down into the band of clouds that circle the equator and then rising up and blowing moisture from the cloud band onto the Sahara desert in the lower right hand corner of the image..
500 mb winds, Nov 12th, 2015
500 mb winds, Nov 12th, 2015

300 mb wind vectors 12.Nov.2015 11:15

Brent

The 500 millibar winds seem to be influenced by the 300 millibar winds which are at about the altitude of the jet stream, and in this image from November 12th, 2015, we can see the same curving pattern.
300 mb wind vectors, Nov. 12th 2015
300 mb wind vectors, Nov. 12th 2015

Water vapor movement 12.Nov.2015 11:17

Brent

The two images above are of 'water vapor' images taken by a certain bandwidth on orbiting satellites, one from earlier in the day and one from midday, and the effects of those 500 millibar winds can clearly be seen as moisture is picked up from the equatorial band and blown onto the desert. The animated gif from the month of September shows what happens when this pattern becomes persistent.
Water vapor 6am Nov 12th, 2015
Water vapor 6am Nov 12th, 2015
Water vapor 3pm Nov 12th, 2015
Water vapor 3pm Nov 12th, 2015

Cold Spot 12.Nov.2015 11:18

Brent

This image shows the cold patch of low temperatures on the Western Sahara.
Cold Temp Anomaly
Cold Temp Anomaly

Topography 12.Nov.2015 11:19

Brent

A topographical map of the same area shows that the region is fairly flat, and some parts are at sea level.
Topography
Topography

Sea Surface Temperature Anomaly 12.Nov.2015 11:20

Brent

The question then is where is this cold temperature coming from. The sea surface temperature anomaly shows that the waters off the coast of the Sahara are warmer than usual, so the Atlantic Ocean could not be the source.
Sea Surface Temperature Anomaly, Nov 12th, 2015
Sea Surface Temperature Anomaly, Nov 12th, 2015

Locked JetStreams 12.Nov.2015 11:21

Brent

If we look again at the 300 millibar map, we can see that the southern polar jet stream is 'locked' together with the Northern polar jet stream and then dives southward towards this cold region on the Sahara, so one possible explanation is that these two jet streams must have been in contact since the middle of September 2015, and that the tropical jet stream has been dragging cold air from the north over the Atlantic and then dumping it onto this region of the Western Sahara for about two months. Unfortunately I have not been able to locate an archive of these images, so for the moment that will have to remain a hypothesis, but it seems to be the most likely explanation (a persistent contact and interaction of these two jet streams as we can see is the case on November 12th, 2015).

Salt Flats 12.Nov.2015 11:22

Brent

There are what appear to be white salt flats just to the south of this cold area, which could be confused with snow blowing through the sand dunes, if it was not for that fact that these are persistent features that have been present for a long time.
White drifts of salt\\\\\\\?
White drifts of salt\\\\\\\?

Glaciers 12.Nov.2015 11:23

Brent

In this false color image we can see three small glaciers which suddenly appeared, becoming big enough to become visible at the lower resolution of this image (and because they were colored blue in the false color image they looked like lakes).
'Lakes'
'Lakes'

Glaciers, Nov 1st 2015 12.Nov.2015 11:24

Brent

These are actually glaciers and not lakes. This is an image of these glaciers as of November 1st, 2015.
Glaciers, Nov 1st 2015
Glaciers, Nov 1st 2015

Snow 12.Nov.2015 11:26

Brent

Here we can see the same glaciers surrounded by a white foggy looking haze on November 11th, 2015. Now this could be a thin cloud cover or even some fog, but we can determine that this is in fact snow on the ground by comparing the features over several days and if the features are persistent they must be snow. This task can be complicated by the fact that the earth is round and so as the Polar Orbital Satellite orbits the earth from the north to the south pole, while the earth spins beneath it, some of the images will be taken along the curve of the earth in various different ways which changes the images. There are two images taken here on different days (November 12th and November 11th).
Nov 11th, 2015
Nov 11th, 2015
Nov 12th 2015
Nov 12th 2015

Snow confirm 12.Nov.2015 11:27

Brent

By comparing the outlines of this white patch we can see that the contours are persistent and this suggests that this area is in fact snow, since either fog or cloudy haze would change shape and only snow would show this persistence in the pattern. The pattern was also not present at the beginning of the month as can be seen in the image from November 1st, 2015.
Confirming snow
Confirming snow

Conclusion 12.Nov.2015 11:27

Brent

So the conclusions I come to are that there must be a persistent 'locking of the tropical and polar jet streams which keeps blowing cold arctic air onto the Sahara, and there is also this persistent pattern of the 500 millibar winds dragging moisture from the equatorial band of clouds and blowing it onto the Sahara desert, and both of these patterns must result in a change in that desert over time.

Adverse Effects on the Amazon 12.Nov.2015 11:33

Brent

One of the consequences of the diversion of the equatorial moisture onto the Sahara is the increase of vegetation stress on the Amazon.
Vegetation stress, Nov 12th, 2015
Vegetation stress, Nov 12th, 2015

Ok! 12.Nov.2015 14:58

Lloyd Hart dadapop@dadapop.com

So the Earth is setting for the next ice age. North Africa is a desert because the last ice age created a European exodus to it that over populated North Africa to the point of leveling it's forests.

Globa Circulation 14.Nov.2015 11:56

Brent

Included is a link to the Global Circulation Video.

In the still image above the arrows show the normal flow pattern of the Intertropical Convergence Zone (the thick band of water vapor that circles the planet near the equator). The normal flow is indicated by the arrows, travelling from Africa to South America and then across the Pacific heading towards Asia.

Global Circulation Video, National Center for Atmospheric Research
Global Circulation Video, National Center for Atmospheric Research

New Circulation Pattern 14.Nov.2015 11:58

Brent

In the image above is a graphic of the 500 millibar winds (at an altitude of cloud level) and I have drawn the new circulation pattern. The circulation comes up from the equator, then turns right and then turns up and then turns right again to push the water vapor and clouds onto the Sahara desert. The westward Pacific flow seems undisturbed, but there are the doldrums with little wind or circulation over the Amazon.
500 mb winds
500 mb winds

Pattern 14.Nov.2015 12:00

Brent

This false color image (highest clouds are the lightest color) shows the pattern, where we can see the clouds being pushed up and onto the Sahara while not much is happening over most of the Amazon.
Nov 15, 2015
Nov 15, 2015

Nature always moves to repair the damage,,,,,, 15.Nov.2015 07:50

Lloyd Hart dadapop@dadapop.com

Humans cause to the earth but this time the Earth wants us to participate in the repair job so we will stop being afraid of the future which causes us to damage the Earth in the first place.

Hunting for Glaciers, Rivers and Lakes 17.Nov.2015 01:53

Brent Herbert

I have discovered that the easiest way to hunt for glaciers on the Sahara is to first look for them on false color images and then locate the corresponding glacier on the higher resolution true color satellite images of the Sahara.
Location 1
Location 1

One 17.Nov.2015 01:55

Brent

One
false color
false color
true color
true color

two 17.Nov.2015 01:57

Brent

two
false color
false color
true color
true color
true color
true color

three 17.Nov.2015 01:59

Brent

three
false color
false color
true color
true color

four 17.Nov.2015 02:00

Brent

four
false color
false color
true color
true color

five 17.Nov.2015 02:03

Brent

an interesting streak down the middle of the desert
false color
false color
true color
true color

lakes rivers snow 17.Nov.2015 02:07

Brent

The following images show some interesting lakes and rivers and odd snow patches out in the middle of the desert.

Rivers and lakes show up as the light greenish color (the lower temperature of the water)
location (red dot)
location (red dot)
false color
false color
true color
true color

rivers 17.Nov.2015 02:10

Brent

The arrow points to the following interesting feature (the blue dot)
Rivers can be seen running in the desert
(pale green color shows the cooler temperature change of the water)

small lakes are also visible
These features are only visible in the false color image
location
location
false color
false color

others 17.Nov.2015 02:11

Brent

there are other examples but these are some of the more interesting examples