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Climate Change Doubles Drought Stricken Area
Cally writes "The National Atmospheric Research Center has published research showing that the percentage of Earth's land area stricken by serious drought more than doubled from the 1970s to the early 2000s, and attributing this to global climate change. Interestingly, the lead author comments that 'droughts and floods are extreme climate events that are likely to change more rapidly than the average climate'."
Or at least the development, farming, clear cutting in those areas has caused it. Places where they measure temperature and rainfall the most are areas that are developed the most. The real question here is are these really long term changes or just natural fluctuations. 5, 30, 100 years are not long term in the scheme of things here.
-- these are only opinions and they might not be mine.
I used to think exactly that until I saw a show on the Discovery Channel about the deep sea current that flows from the North Atlantic to the SW Pacific.
Yes, my source is a TV show.
It clearly explained (in terms a CS guy could understand) how the threat of global warming is NOT rising temperatures and rising sea levels, but rather a decrease in the salinity of the North Atlantic which will disrupt the deep sea current. The result of this will be a dramatic and nearly immedate end to the moderation of climates enjoyed around the world - basically everywhere north of the Tropic of Cancer and south of the Tropic of Capricorn will experience an ice age while the equatorial region will become a desert that makes the Sahara look quaint.
I'm not prepared to argue the merits or weaknesses of such conjecture, but The Discovery channel sure as hell convinced me - to my (climatology amateur yet) analytical mind, the arguments all stacked up. The salinity situation is all but impossible to refute and the climate data culled from Antarctic glacier ice cores indicates that sudden radical shifts in Earth's climate into an ice age are nothing if not typical.
By the way - if somebody knows what I'm talking about and has a good link to the material, I'd love to see it. Telling people about the TV show I saw that one time gets old.
I was supprised that this article doesn't mention the effect of land use over climate change. One of the fastest ways the increase the local tempeture of an area is to cut down all the trees (raise by 2-3 degrees C). Remember over=grazing of the mid west led to the dust bowl during the great depression. Sadly a lot of developing nations use bad farming practaces, and that is why deserts are the only ecosystems still expanding today.
Ugh...global warming does not mean the earth temperature increases everywhere by the same amount. It changes weather patterns. Some places may get hotter, other colder. Some places may flood, others experience a drought.
I mean I know the phrase "global warming" sounds like the temperature everywhere will just increase by a degree or so, but jesus christ, why doesn't anyone ever take a few moments out to learn what it really does before forming an opinion on it.
I have not seen the show, but I have read about what you are talking about. A current theory is that Lake Agassiz, a 'super great lake', catastrophically drained into the upper Atlantic causing a shift in salinity, thus a shift in the temperature current flow, thus a shift in climate. Ref: http://scienceweek.com/2003/sw030627.htm
All this talk about historic climate change is like an ant talking about the nature of an elephant. We are too small, and the details are too big. To hear environmentalists talk about it, we are on the verge of disaster, but to hear geologists talk about it, we are just barely coming out of the last ice age. From a geological standpoint, everything I have read about says that our planet should be about 10 degrees warmer than what it is today. We're coming out of 'abnormal' climtes, and apparently inching back toward 'normal'. A google on "cenozoic ice age" will be instructive, as is this page: http://www.museum.state.il.us/exhibits/ice_ages/ "During most of the last 1 billion years the globe had no permanent ice." North and south pole ice is an anomaly.
By the way - if somebody knows what I'm talking about and has a good link to the material, I'd love to see it. Telling people about the TV show I saw that one time gets old.
Google the following:
Thermohaline Circulation
Younger Dryas
Lake Agassiz
If deep convection in the Labrador/Greenland sea ceases, the Gulf Stream will cease and England will get mighty chilly. Roughly speaking, if you don't have cold, salty water sinking downward in this region, no surface currents will move to fill the void (kind of like plugging the drain in the bathtub).
As the northern hemisphere began coming out of the last glacial maximum about 13,000 years ago, it abruptly became colder again - slammed back into the cold regime. A leading hypothesis as to why this occurred is that a lot of ice was melting in modern-day Canada the northern US and forming a large lake (Lake Agassiz). Suddenly, the dam broke (probalby down the St. Lawrence) and a gazillion gallons of fresh water was spilled into the North Atlantic, creating a freshwater "lid" which kept the surface waters from getting dense enough to convect downward like they do sporadically today.
I did some post-doc modeling research on deep convection in the Greenland Sea. Neat stuff. There are only a very few places where this sinking occurs in the ocean, and without it the climate of the world would be much different.
A squid eating dough in a polyethylene bag is fast and bulbous, got me?
Yes. For there is no physical fact known to absolute certainty. None. Not one. Absolute truths are limited to geometry, mathamatics and logic. Gravity, speed of light, any idea based on measurements, all such ideas are are all subject to doubt. But I would not suggest jumping of any tall buildings. The odds are very very high that such a jumper would become a messy spot on the ground in just seconds.
Climate is a complex subject. Understanding it would be very unlikely to help you get an audition on the "O'Reilly" factor. It would be more likely to keep you off such shows. But if you did want to understand, here is the best overview I know of:
http://www.grida.no/climate/ipcc_tar/wg1/index.htm
About 100 years ago, the "liberals" would have been the ones arguing that all changes are gradual in response to conservative nut cases talking great floods and cataclysmic events. Today, the conservatives seem to shut their eyes to the possibility of catastrophic changes, and the liberals are more likely to be talking about catastrophic change.
The world is a lot stranger than "liberal" vs "conservative". While climate change will probably look sudden on a geological time scale, on a human scale it probably will not look catastrophic until it is catastrophic. Which is exactly too late. Isn't preventing change what "conservatives" try to do?