jimgandy
Reply with quote #1 If you are looking for information on the rise of global sea level, there is a report published in the November 2009 issue of the Journal of Climate worth noting. The reference is: Merrifield, M.A., S.T. Merrifield, and G.T. Mitchum, 2009: An Anomalous Recent Acceleration of Global Sea Level Rise. J. Climate 22 Abstract: Tide gauge data are used to estimate trends in global sea level for the period from 1955 to 2007. Linear trends over 15-yr segments are computed for each tide gauge record, averaged over latitude bands, and combined to form an area-weighted global mean trend. The uncertainty of the global trend is specified as a sampling error plus a random vertical land motion component, but land motion corrections do not change the results. The average global sea level trend for the time segments centered on 1962–90 is 1.5 ± 0.5 mm yr-1 (standard error), in agreement with previous estimates of late twentieth-century sea level rise. After 1990, the global trend increases to the most recent rate of 3.2 ± 0.4 mm yr-1 , matching estimates obtained from satellite altimetry. The acceleration is distinct from decadal variations in global sea level that have been reported in previous studies. Increased rates in the tropical and southern oceans primarily account for the acceleration. The timing of the global acceleration corresponds to similar sea level trend changes associated with upper ocean heat content and ice melt.
The full story is available at:
http://ams.allenpress.com/perlserv/?request=get-toc&issn=1520-0442&volume=22&issue=21 Loading...
jimgandy
Reply with quote #2 In addition, there is a paper just published in the Geophysical Research Letters that looks at sea level variability over the past 1000 years. The study examines the causes for the fluctuations. Citation: Jevrejeva, S. , A. Grinsted, and J. C. Moore2009 ), Anthropogenic forcing dominates sea level rise since 1850 , Geophys. Res. Lett. 36 Abstract: The rate of sea level rise and its causes are topics of active debate. Here we use a delayed response statistical model to attribute the past 1000 years of sea level variability to various natural (volcanic and solar radiative) and anthropogenic (greenhouse gases and aerosols) forcings. We show that until 1800 the main drivers of sea level change are volcanic and solar radiative forcings. For the past 200 years sea level rise is mostly associated with anthropogenic factors. Only 4 ± 1.5 cm (25% of total sea level rise) during the 20th century is attributed to natural forcings, the remaining 14 ± 1.5 cm are due to a rapid increase in CO2 and other greenhouse gases. Loading...
