I am reminded of a February 2007 post over at Climate Audit on a Simon Holgate sea level changes paper published in GRL, and a related poster presentation. Holgate claimed that sea levels rose more in the first half of the 20th century, than in the second half. The same could be said for solar activity.
Plotting the sun spot data on to Holgate’s graph of sea level changes produces an interesting result:
Holgate 2007 Figure 2. Comparison of the global mean decadal rates of sea level change based on the nine records with the rates from the 177 stations used in HW04. All rates are corrected for glacial isostatic adjustment and inverse barometer effects. The shaded region indicates standard error. The sun spot numbers are from here.
The coincidence is good except for the last sunspot cycle. Note also that the sea level series are decade mid-point, so the sunspot series should be read as displaced 5 years to the left. Does this mean that the correlation is real, but the effect of CO2 or something else has become apparent during the last solar cycle? Who knows!?
Whilst on the subject of sea level rise, there is this graph below from NASA-GISS: Sea Level Rise, After the Ice Melted and Today
MWP = meltwater pulse. MWP-1A0, c. 19,000 years ago, MWP-1A, 14,600 to 13,500 years ago, MWP-1B, 11,500-11,000 years ago, MWP-1C, ~8,200-7,600 years ago.
I think the above graph puts modern sea level rise into perspective.
References:
S. J. Holgate, On the decadal rates of sea level change during the twentieth century. GRL, 2007.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Paul: This Holgate update is more in line with Peter Helman downunder
“The IPCC’s estimates are regarded as conservative in the scientific community,” Simon Holgate, also of Proudman, said.
http://news.smh.com.au/seas-may-rise-faster-than-un-believes/20080416-26iu.html
Helman from the Griffin Center for Costal Management is reported in yesterday’s Canberra Times as saying “the next ten years could be a disaster for Australia’s east coast”
http://fennerschool.anu.edu.au/news_events/seminars/helman_apr2008.php
“The court’s decision is believed to be the first time sea level impact has been considered. The court heard the shoreline would erode inland by up to 40m over 100 years, affecting an erosion buffer zone and a coastal reserve in the council’s development plan”
http://www.news.com.au/adelaidenow/story/0,22606,23417987-2682,00.html
Time and tide wait for none
RICK Birchmore has lived by the beach all his life. In that time, he has seen the effect of sea level rise first-hand.
“Mr Birchmore, 59, of Hallett Cove, has been the leaseholder of the beachfront Brighton Caravan Park and Holiday Village at Kingston Park for the past 27 years.
He said where once he didn’t bat an eyelid at king tides, now the spray from the big tides hits the front of the park. About 10 years ago he stopped putting caravans at the front of the park during high tides.
“There have certainly been some changes over the decades,” he said. “Twenty-seven years ago you felt real safe in the park”
Gavin, some parts of the South Australian coastline are rising, and some sinking. Much of the SE coastline is naturally sinking. The SA coatline along the Great Australian Bight is slowly rising. These are geological processes.
Opps typo.. The SA coastline …
“In Adelaide, the ground is going down as well as the sea going up, so Venice is a window on the future for Adelaide,” Dr Cowell told the Sunday Mail. “So in 100 years from now, while the global sea level is likely to be about half a metre higher, in Adelaide it will be a metre higher”
I more interested in what people think about the solar cycle correlation rather than playing King Canute.
I managed to track down the Woodworth paper:
A world-wide search for the 11-yr solar cycle in mean sea-level records
Philip L. Woodworth Institute of Oceanographic Sciences, Bidston Observatory, Birkenhead, Merseyside
Abstract
Summary. Tide gauge records from throughout the world have been examined for evidence of the 11-yr solar cycle in mean sea-level (MSL). In Europe an amplitude of 10–15mm is observed with a phase relative to the sunspot cycle similar to that expected as a response to forcing from previously reported solar cycles in sea-level air pressure and winds. At the highest European latitudes the MSL solar cycle is in antiphase to the sunspot cycle while at mid-latitudes it changes to being approximately in phase. Elsewhere in the world there is no convincing evidence for an 11-yr component in MSL records.