Imagens de satélite interessantes

Thomar

Cumulonimbus
Registo
19 Dez 2007
Mensagens
2,915
Local
Cabanas - Palmela (75m)
Bela imagem da depressão para mais tarde recordar:

mFrqImD.png
 


guimeixen

Cumulonimbus
Registo
5 Jun 2013
Mensagens
2,376
Local
Ferreiros, Braga 160m
uma pergunta porque é que a região do Algarve esta com contorno e o resto das regiões não

Não sei apenas selecionei a opção para aparecerem as linhas da costa e fronteiras e ficou assim. Foi tirada daqui a foto: Nasa World View
 

TiagoLC

Super Célula
Registo
15 Jul 2015
Mensagens
7,338
Local
Carnaxide, Oeiras
E o inevitável começa a acontecer...
19/05/2016
TyFSXWz.jpg

19/06/2016
qXfXPre.jpg

Em apenas 1 mês, os campos alentejanos já secaram com a falta de chuva dos últimos dias, mas não é nada de anormal para esta altura do ano, até continua a ser bastante bom e temos que nos lembrar que o país se manteve "verdinho" durante bastante tempo. :D
 

guisilva5000

Super Célula
Registo
16 Set 2014
Mensagens
7,114
Local
Belas
Nevoeiro de ontem:

Esta primeira foto deve ter sido tirada depois do meio-dia, onde a Fonte da Telha ainda estava "poupada" pelo nevoeiro. Estranho remoinho:

yyPyWIS.png


Nesta imagem vê-se melhor que as praias abaixo de Peniche estavam mergulhadas em nevoeiro, provavelmente ainda de manhã:

ONHXfJc.png


Infelizmente o satélite não tira fotos mais à tarde, hora em que o nevoeiro piorou consideravelmente.
 

Vince

Furacão
Registo
23 Jan 2007
Mensagens
10,624
Local
Braga
Making Waves in the Sky off of Africa

ibSAdms.jpg


download large image (8 MB, JPEG, 8000x8000)
acquired June 26, 2016download GeoTIFF file (85 MB, TIFF, 8000x8000)



On June 26, 2016, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired this natural-color image of cloud gravity waves off the coast of Angola and Namibia.

“I [regularly] look at this area on Worldview because you quite often have these gravity waves,” said Bastiaan Van Diedenhoven, a researcher for Columbia University and NASA's Goddard Institute for Space Studies interested in cloud formations. “On this day, there was so much going on—so many different waves from different directions—that they really started interfering.” A distinctive criss-cross pattern formed in unbroken stretches hundreds of kilometers long.

Similar to a boat’s wake, which forms as the water is pushed upward by the boat and pulled downward again by gravity, these clouds are formed by the rise and fall of colliding air columns.

Off of west Africa, dry air coming off the Namib desert—after being cooled by the night—moves out under the balmy, moist air over the ocean and bumps it upwards. As the humid air rises to a higher altitude, the moisture condenses into droplets, forming clouds. Gravity rolls these newly formed clouds into a wave-like shape. When moist air goes up, it cools, and then gravity pushes it down again. As it plummets toward the earth, the moist air is pushed up again by the dry air. Repeated again and again, this process creates gravity waves. Clouds occur at the upward wave motions, while they evaporate at the downward motions.

Such waves will often propagate in the morning and early afternoon, said Van Diedenhoven. During the course of the day, the clouds move out to sea and stretch out, as the dry air flowing off the land pushes the moist ocean air westward.

In this image, the clouds form several hundred kilometers off the coast, but at times when the air is less dry or westerly winds are less strong, clouds can be seen hugging the coast.

NASA Earth Observatory image by Jesse Allen, using data from the Land Atmosphere Near real-time Capability for EOS (LANCE). Caption by Pola Lem.

Instrument(s):
Terra - MODIS
http://earthobservatory.nasa.gov/IOTD/view.php?id=88296