Afghanistan Dust Storm 20th December 2011: NASAs Image of the Day!

Sorry this is a slight diversion from the current theme! Here is a picture I found on NASA's Earth Observatory Website under the image of the day section. Although its not relevant to what i've been talking about in recent weeks its a very interesting image and important for what I have previously discussed on dust.

The accompanying text goes as follows:

"A dense cloud of dust swept across southern Afghanistan and Pakistan on December 20, 2011. When the Moderate Resolution Imaging Spectroradiometer (MODIS) took this image from the Terra satellite at 10:45 a.m., the dust was largely hemmed in by the Makran and Sulaiman Ranges in Pakistan with only a few wisps reaching south over the Arabian Sea. By the time Aqua MODIS flew over just three hours later, the storm had reached the coast. The dust storm continued on December 21.

The storm is being propelled by strong winds from the north. The winds picked up dust from dry lakebeds in the Hamun wetlands, on the border between Afghanistan and Iran. Concentrated plumes of dust rise from the pale wetlands to become a more diffuse cloud in the south and east. Dry lakebeds and wetlands are among the most common sources of dust in the world.

Dust storms can happen any time of the year in Afghanistan. On average, Afghanistan experiences blowing dust one to two days per month in the winter and six days per month at the height of the summer. Zabon, an Iranian city located near the border in the Hamun wetlands, reports 81 dust storms per year.

Blowing dust poses a hazard to transportation, as low visibility closes roads and airports. This particular storm prevented British Prime Minister David Cameron from visiting a British military base because the runway was closed for low visibility."

The reason for pasting this is to draw your attentions to a couple of sentences in particular that reinforce some of what I have said on dust and some of the more abstract theories with a real world example. From the first paragraph it is clear that the dust storm has travelled a considerable range, increasing its potential to affect a whole host of systems, both environmental and human. The dust in this example was sourced from another dry lake bed and wetlands, not dissimilar from the type of source that contributed the most dust to the system in Africa that I touched upon. Finally, the last paragraph highlights just one of the ways in which can affect human lives and operations....

Apologies for the interjection, I just thought this was a neat example that ties up some of the dust posts.