Thursday, May 24, 2012

Famed hurricane forecaster Dr. William Gray predicts below-average hurricane activity for 2012 & global cooling over next 20 years

Famed hurricane forecaster Dr. William Gray has issued his hurricane season forecast for 2012 and predicts below-average probability for major hurricanes making landfall.  Dr. Gray is Professor Emeritus, Dept of Atmospheric Science, Colorado State University and a skeptic of man-made global warming. Dr. Gray contends that the global ocean's natural Meridional Overturning Circulation (MOC) "is the likely cause of most of the global warming that has been observed since the start of the industrial revolution (~1850) and for the more recent global warming that has occurred since the mid-1970s." In his paper, "Climate Change: Driven by the Ocean not Human Activity," Dr. Gray notes that observations show tropospheric water vapor has decreased with increased CO2, the opposite of the assumptions programmed into climate models, thus, "The predicted global warming due to a doubling of CO2 has been erroneously exaggerated by the [climate models] due to this water vapor feedback."

Abstracts from Dr. Gray's papers:

Climate Change: Driven by the Ocean not Human Activity

Abstract: This paper discusses how the variation in the global ocean’s Meridional Overturning Circulation (MOC) resulting from changes in the Atlantic Thermohaline Circulation (THC) and deep water Surrounding Antarctica Subsidence (SAS) can be the primary cause of climate change.   (MOC = THC + SAS) is the likely cause of most of the global warming that has been observed since the start of the industrial revolution (~1850) and for the more recent global warming that has occurred since the mid-1970s.  Changes of the MOC since 1995 are hypothesized to have lead to the cessation of global warming since 1998 and to the beginning of a weak global cooling that has occurred since 2001.  This weak cooling is projected to go on for the next couple of decades.

Recent GCM global warming scenarios assume that a slightly stronger hydrologic cycle (due to the increase in CO2) will cause additional upper-level tropospheric water vapor and cloudiness.  Such vapor-cloudiness increases are assumed to allow the small initial warming due to increased CO2 to be unrealistically multiplied 2-4 or more times.  This is where most of the global warming from the GCMs comes from – not the warming resulting from the CO2 increase by itself but the large extra warming due to the assumed increase of upper tropospheric water vapor and cloudiness.  As CO2 increases, it does not follow that the net global upper-level water vapor and cloudiness will increase significantly.  Observations of upper tropospheric water vapor over the last 3-4 decades from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data and the International Satellite Cloud Climatology Project (ISCCP) data show that upper tropospheric water vapor appears to undergo a small decrease while Outgoing Longwave Radiation (OLR) undergoes a small increase.  This is opposite to what has  been programmed into the GCMs.  The predicted global warming due to a doubling of CO2 has been erroneously exaggerated by the GCMs due to this water vapor feedback.

CO2 increases without positive water vapor feedback could only have been responsible for about  0.1-0.2o C of the 0.6-0.7o C global mean surface temperature warming that has been observed since the early 20th  century.  Assuming a doubling of CO2 by the late 21st  century (assuming no  positive water vapor feedback), we should likely expect to see no more than about 0.3-0.5oC global surface warming and certainly not the 2-5oC warming that has been projected by the GCMs. 

Remainder here


EXTENDED RANGE FORECAST OF ATLANTIC SEASONAL HURRICANE ACTIVITY AND LANDFALL STRIKE PROBABILITY FOR 2012

We anticipate that the 2012 Atlantic basin hurricane season will have reduced activity compared with the 1981-2010 climatology.  The tropical Atlantic has anomalously cooled over the past several months, and it appears that the chances of an El NiƱo event this summer and fall are relatively high.  We anticipate a below-average probability for major hurricanes making landfall along the United States coastline and in the Caribbean.  However, coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them, and they need to prepare the same for every season, regardless of how much activity is predicted.

1 comment:

  1. Well I suggested the thermohaline circulation as a contributor to the late 20th century warming some years ago.

    I have also incorporated it into a New Climate Model which suggests that a period of high solar activity injects more energy into the oceans so as to introduce temperature variations along the horizontal track of the thermohaline circulation which surface some 800 to 1000 years later as per ice core evidence.

    For a fuller description see here:

    http://wattsupwiththat.com/2010/04/06/a-new-and-effective-climate-model/

    Stephen Wilde

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