Sunday, March 28, 2010

Rates of Sea Level Rise

One of the claims by the Holocene denying climate alarmists is that the sea levels are rising faster now, due to man, than at anytime in geologic history.

An abstract in Nature Geoscience says:

Nature Geoscience
Published online: 14 June 2009 | doi:10.1038/ngeo544
Identifying the causes of sea-level change
Glenn A. Milne1, W. Roland Gehrels2, Chris W. Hughes3 & Mark E. Tamisiea3

Abstract
Global mean sea-level change has increased from a few centimetres per century over recent millennia to a few tens of centimetres per century in recent decades. This tenfold increase in the rate of rise can be attributed to climate change through the melting of land ice and the thermal expansion of ocean water. As the present warming trend is expected to continue, global mean sea level will continue to rise. Here we review recent insights into past sea-level changes on decadal to millennial timescales and how they may help constrain future changes. We find that most studies constrain global mean sea-level rise to less than one metre over the twenty-first century, but departures from this global mean could reach several decimetres in many areas. We conclude that improving estimates of the spatial variability in future sea-level change is an important research target in coming years.


But such rates as mentioned in that article are not unusual, nor are they outside of the rate of natural variation. A recent study in Science studied the cave deposits in Mallorca and showed that the rates of sea level rise were as great as 20 m/1000 years, or 2 meters per century. And this was over 80,000 years ago when no automobile or coal-fired electrical plant existed.

"Specifically at Mallorca, speleothem
encrustations record a MIS 5b sea-level height of
~ –20 m at 85.4 +/- 0.9 ka and a MIS 5a height of
~ +1 m by 84.2 +/- 1.0 ka (10). The sea-level
drop after the MIS 5a highstand was very rapid
as well, because speleothem encrustations
record a height of ~ –15 m by ~78.6 +/- 0.8 ka
(10). These rates of sea-level change nominally
approach 20 m per thousand years..."
Dorale, et al, “Sea-Level Highstand 81,000 Years Ago in Mallorca”, Science, Feb 12, 2010, p. 861






That huge variation occurred without any human interference, yet the IPCC wants us to claim credit for raising the oceans at a rate of 3.1 millimeters per year (.3 m/century) when history shows that the oceans have naturally varied at 6 times the rate that the IPCC says should be blamed on us.


"Global average sea level rose at an average rate of 1.8
[1.3 to 2.3] mm per year over 1961 to 2003. The rate
was faster over 1993 to 2003: about 3.1 [2.4 to 3.8]
mm per year. Whether the faster rate for 1993 to 2003
refl ects decadal variability or an increase in the longerterm
trend is unclear."
source IPCC AR4 WG1p. 5

The Holocene denying, anti-geological hysteriacs should look to see what the history of the earth really shows.

2 comments:

  1. this topic is a great controversy because there are studies that they try to prove that there aren't such thing as a global warning. I think that it is real and they don't want to do something about it.

    ReplyDelete
  2. Yeah something new... the human race is destroying the planet, but well someday the planet is gonna pas us the bill as it is doing now.

    ReplyDelete