The National Center for Atmospheric Research in Boulder Colorado and NASA’s Jet Propulsion Laboratory, funded by the National Science Foundation, have been taking a serious look at some radically crazy sea level rise figures. It seems that the Australian Outback has taken over sea level rise. Those widespread floods that ended (temporarily?) Australia’s latest 10-year drought had widespread global impacts.
Those floods that ended the Australian drought in 2010/11 had some really unexpected results. It’s so flat in the Outback that the floodwaters just sat there and soaked in. It rained so much and the ground was so dry from ten years of drought that little of the water ran off into the oceans.
You remember that great old saying” You can’t fight gravity.” Well, You may not be able to fight gravity, but you can change it. Our satellites have become so sensitive that they could tell. When all of that extra water was added to Earth’s surface on that one small continent it changed Earth’s gravity.
A rare combination of two weather cycles caused the floods. La Nina and the Southern Annular Mode (A southern Hemisphere atmospheric circulation pattern) came together and then stalled out. The the Indian Ocean Dipole mode collided and hell broke loose– very exciting stuff if one is a meteorologist, believe me.
The results were all that water that fell in the Outback didn’t go anywhere after it fell and “`lowered sea level rise by 7 mm in 18 months. Since the normal rise was 3 mm per year, the average sea level across the planet actually fell a millimeter or two during that short period.
The Grace Satellites and the Argo sea level rise buoy system were the key players in this research. The Grace Satellites measure gravity, were launched in 2003, and are 100 times more sensitive than the previous gravity measuring satellites. the Argo Buoy Array system is unlike anything before. It was totally functional with 3,000 buoys in 2007. The bob up an down a mile in the oceans of the world every ten days measuring temperature, density, pH, salinity and sea level.
The last time something like this could have happened was in 1973/4, but scientists are not sure. These fabulous earth observation systems were really not even dreams back then. This was a rare event regardless.
What has happened since? Normal sea level rise since the turn of the century has been 2 to 3.7 mm per year, depending on whose research is being reported. Around the turn of the century less, more recently more. prior to the turn of the century the 20 century average, up until 1990 , was between 1.2 and 1.5 millimeters per year.
The authors of this report tell us one more thing that we knew was coming. Since it quite raining in Australia in 2011, level rise has jumped to 10 mm per year—nearly, or more than three times what sea level rise was before this Outback event.
Is sea level rise just catching up, or did the record melt in Greenland in 2010, 2011 and 2012 have something to do with this?
NSF Press Release:
http://www.nsf.gov/news/news_summ.jsp?cntn_id=128842&org=NSF&from=news