[thedoc (OP)]

Researchers at the University of Leeds have found that an Amazonian drought in 2010 was more severe that one billed as a 'once in a century' event in 2005, and this could have big implications for the ability of the Amazon to act as a carbon sink...

Read the whole story on our website by clicking here

 [chapter podcast=3002 track=11.02.06/Naked_Scientists_Show_11.02.06_7861.mp3] or Listen to the Story[/chapter] or [download as MP3]

[thedoc (OP)]

[CliffordK]

My first question is rain that is not falling in the Amazon...  is it just not falling... or is it being displaced elsewhere.  In particular, is there any displacement of the water into dryer regions?

2010 was listed as having the highest global rainfall in a century.  In fact some of the Aussies were complaining about having too much rainfall in 2010.  2005 is also listed as having an above average global annual rainfall, although not as intense.

http://www.ncdc.noaa.gov/sotc/global/2010/13


There is a correlation between the low rainfall and the El Niño ocean currents.
http://www.esrl.noaa.gov/psd/people/klaus.wolter/MEI/


So, the 2010 trend was likely brief... and likely has already been reversed.

There seems to be somewhat more prevalent El Niño currents in since about 1980.  But, it is perhaps early to tell if it is a statistical anomaly, and/or whether they have Anthropogenic causes.

One would also have to ask if these are actually "100 year droughts"...  as there are many indications of a significant Amazon drought in 1926, and perhaps a somewhat smaller drought in 1936, a decade later, as well as significant river flow fluctuations throughout the past century.  1906?  1912?  1963?  1992?  1995?  1998?

http://journals.ametsoc.org/doi/pdf/10.1175/2007JCLI1600.1
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There will likely be some benefits if there is a displacement of water from the Equator towards the Tropic of Cancer and Tropic of Capricorn.

In fact, there seems to be somewhat of an anti-correlation between the Amazon River and the Parana River (into southern Brazil and Northern Argentina.



In the 2010 Global map, you can see the Parana basin was wet. 
Also compare:
50's and 60's, low flow Rio Negro, high flow Parana
Late 60's...  very distinctive high flow Amazon, low flow Parana

It would also be interesting to see a comparison of the flows between the Nile and the Amazon, for example.