New study shows Gulf Stream increasing in strength

[Nederland]

http://www.nasa.gov/topics/earth/features/atlantic20100325.html

In 2005, close on the heels of the movie The Day After Tomorrow, a paper was published (http://www.nature.com/nature/journal/v438/n7068/full/nature04385.html) that showed that the Atlantic Meridional Overturning Circulation (AMOC) had declined in strength by 30 percent since the 1950s, and was predicted to decline even further in the coming decades. Computer models predicted that global warming could switch off the North Atlantic current within the next 50 to 100 years. Articles like this (http://news.nationalgeographic.com/news/2005/11/1130_051130_ice_age.html) National Geographic article reported on the possible dire consequences for northern Europe, which depends on the current to create a climate that is relatively warming given its latitude.

Now it turns out the paper and the computer models were all wrong.

The original study, which was based upon an absurdly small number of measurements, was recently shown to have reached exactly the wrong conclusions. A new study, based upon data gathered from the ARGO array (http://www.argo.ucsd.edu/How_Argo_Floats.html), definitively shows that the the AMOC has not changed for the period 2002-2009, and according to satellite measurements increased in strength by over 2.4 million m3/s since 1993.

http://www.agu.org/pubs/crossref/2010/2010GL042372.shtml

Global warming has been predicted to slow the Atlantic Meridional Overturning Circulation (AMOC), resulting in significant regional climate impacts across the North Atlantic and beyond. Here, satellite observations of sea surface height (SSH) along with temperature, salinity and velocity from profiling floats are used to estimate changes in the northward-flowing, upper limb of the AMOC at latitudes around 41°N. The 2004 through 2006 mean overturning is found to be 15.5 ± 2.4 Sv (106 m3/s) with somewhat smaller seasonal and interannual variability than at lower latitudes. There is no significant trend in overturning strength between 2002 and 2009. Altimeter data, however, suggest an increase of 2.6 Sv since 1993, consistent with North Atlantic warming during this same period. Despite significant seasonal to interannual fluctuations, these observations demonstrate that substantial slowing of the AMOC did not occur during the past 7 years and is unlikely to have occurred in the past 2 decades.

The difference between the two studies can be attributed to one thing: the quality and quantity of data used in the analysis. The original 2005 paper was based upon a small handful of ship measurements and readings from moorings anchored to the ocean floor. In comparison, the new study is based upon satellite data and data from the ARGO array whose 3000+ floats report precise position, temperature and salinity readings every 10 days.

The impact that the new findings will have on the GCMs used to predict future climate change is at this point unknown. However, the fact the current models got the prediction of what would happen to the AMOC exactly backwards cannot serve to increase the scientific community's confidence in their accuracy. The ocean contains 5 times as much heat as the atmosphere, and modeling of the entire climate cannot possible be done accurately without first accurately modeling ocean currents.

[pscot]

1. ARGO is truely amazing

It brings to bear the best our technology offers to provide continuous accurate monitoring of what's happening to the oceans. Great stuff.

[bananas]

2. The Day After Tomorrow was ghost-written by aliens

Whitley Streiber said the aliens told him the story.
I heard him say that on Art Bell's show long ago.
It's also in wikipedia:

http://en.wikipedia.org/wiki/Whitley_Strieber

Before publishing The Key, Strieber co-authored, with Art Bell, The Coming Global Superstorm (1999), a book about the possibility of rapid and destructive climate change. He has said that it was based largely on things the Master of the Key had told him about the environment. The book served as the inspiration for the disaster film The Day After Tomorrow (2004) and Strieber later wrote a novelization of that movie.

:popcorn:

[troubledamerican]

3. Wikipedia: Collapse of Thermohaline Circulation

http://en.wikipedia.org/wiki/Shutdown_of_thermohaline_circulation

[Nederland]

4. It will be interesting to see...

...how long it takes someone to update the Wikipedia page with the latest information. It will also be interesting to see what excuses are made to explain why the IPCC models got everything so very wrong.