Recent haboob in Phoenix, Az.
Yet another scientific mystery is unfolding around the globe. Meteorologists are baffled as to the cause of giant sand and dust storms (haboobs) that are sweeping across arid regions and deserts....and still more haboobs that are now appearing outside of deserts. A recent newspaper article about the haboobs was headlined:
"Mystery of the dust storms sweeping the world: Experts baffled by spate of 'haboobs' which have brought travel chaos and turned day into night in cities thousands of miles from deserts
The newspaper went on to report:
"This year has seen a rash of massive dust storms around the world that have led to travel chaos and blocked out sunlight - but experts cannot pinpoint the reason...."
Take a deep breath, count to ten, and repeat after me: global warming is responsible for producing more haboobs. In fact, these giant dust storms should be seen as a form of proxy climate data. Larger and more frequent dust storms are exactly the sort of thing that one would expect to see more of if the world was undergoing global warming, and if drought and aridification was occurring over larger and larger regions. If water tables were falling and areas of bare ground were growing, if rain was falling less often and temperatures were growing warming, then you might expect more dust storms. And that is exactly what is happening.
So why oh why are meteorologists puzzled by the abundance of large dust storms just now? It turns out to be very difficult to quantify something like global warming just using weather records because weather itself is so extremely variable. Most attempts to quantify the amount of global warming going on now are just based on instrumental readings of temperatures, and this kind of data shows the earth has warmed about 1 to 1.5°C over the last 150 years. However, if you only consider temperature, then you don't capture variations in cloud cover, wind and rainfall intensity, changes in seasons, humidity, and other weather phenomena that are also responding to global climate change.
That where proxy climate records come in handy. Natural features like glacier extents and river discharge grow or shrink in response to a whole suite of climate data ---- not just changes in temperature. Things like changes in glacier extents and river discharge provide an alternative proxy measure that integrates all the various aspects of climate changes currently affecting them.
Haboobs are another natural phenomena that will change in frequency and intensity in response to global warming. Its very difficult to quantify exactly how much more haboob activity is occurring now then in the past, because these events are not being consistently tracked on a global basis. To make it even more difficult, haboobs are called by a variety of names including dust storms in some areas of the world and sand storms in other areas. But there should be little doubt that ongoing global warming is responsible for the increasing frequency of haboobs we are currently seeing, and one would have to be a boob not to associate the haboobs with global warming.
Recent haboob in Lubbock, Texas
Recent haboob in eastern Washington State
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