Posts Tagged ‘IPCC’


Uh, Oh! Karl, et. al., is bad news for Stefan Rahmstorf’s sea level rise rate.

September 25, 2015

Conclusion first

When the 20th century GISS temperature is modified according to Tom Karl,, it causes the 21st century sea level predictions of Vermeer’s and Rahmstorf’s semi-empirical model to go down!


I have written extensively about “Global sea level linked to global temperature,” by Vermeer and Rahmstorf (which I will refer to as VR2009).

VR2009 was a widely cited claim of using historical 20th century sea level and temperature data to calculate parameters that could be used to build a model to predict 21st century sea level rise for various 21st century temperature scenarios.  I reproduced the VR2009 model based on their description.  My code was verified by reproducing the VR2009 results using the same inputs that they used.

I spent a lot of time pointing out some of the bizarre results of their model that surely disqualified it form being taken seriously, some of which can be seen here, here, and here.

I also spent a lot of time pointing out that the VR2009 choices of 20th century sea level data sources left much to be desired.  For example, they used the 2006 Church and White sea level data that was already outdated.  If they had used the revised Church and White data, then their resulting sea level rise predictions for the 21st century would have been much lower.

They happily modified Church’s and White’s outdated sea level data by subtracting a reservoir correction (Chao, et. al.), which made their 21st century predictions for sea level rise go up. But they made no attempt to estimate a groundwater depletion correction. It turns out, unsurprisingly, that the groundwater depletion is of the same magnitude as the reservoir correction (Wada, et. al.), and including it would have made their 21st century predictions go down.

Nevertheless, Rahmstorf would later claim that his modeling approach was “robust!”  That is, it would give essentially the same result for the 21st century given different sources of 20th century sea level data.

So, I also implemented the VR2009 technique using several different sources of sea level data, which should have given similar results, according to Rahmstorf’s claim of robustness.  In fact, they gave widely varying results, and every combination of sea level data, reservoir data, and groundwater depletion data that I tried gave lower results than VR2009’s chosen combination.

New Temperature Data!

The widely reported nearly two decade long pause in global warming was causing suicidal ideation among hard-core global warming alarmists.  Something had to be done to stop them from slitting their wrists with shards of glass from their shattered thermometers.

Just in the nick of time – revised temperature data!   Like all proper revisions of temperature data, this revision caused the reported temperature change of the 20th century to go up.

This was a result of a paper by Tom Karl, et. al. (Nature) based on very thin reasoning (see for example) that argued for such revision.  The folks at GISS (who provided VR2009’s temperature data) glommed onto Karl’s logic and subsequently revised their temperature data accordingly.  Other temperature data source like UAH and RSS did not.

Which means we must ask ourselves, what happens to 21st century sea level rise predictions based on the VR2009 model using the now modified GISS data?

VR2009 applied their model to six families of temperature scenarios for the 21st century form the IPCC’s 4th Assessment Report.  Let’s see what happens to each of those scenarios when we update the 20th century GISS temperature data.

The IPCC temperature scenarios that VR2009 used for prediction of 21st century sea level rise.

Case 1.

Sea level inputs are identical to what VR2009 used: Church’s and White’s sea level with the Chao reservoir correction.  The old GISS temperature data is replaced with the new GISS temperature data.  The table below shows that the new GISS data yields 21st century sea level rises that are about 17% less than when the old GISS data is used.

Old GISS vs New GISS

It is a shame that after Tom Karl went to all the trouble to increase the temperature rise of the 20th century it just makes VR2009’s model predict LOWER sea levels for the 21st century.  This must be a great disappointment to Vermeer and Rahmstorf, so you can be pretty sure they will never tell you this result. But I just did.

Case 2

As I pointed out previously, VR2009 chose to use outdated 2006 Church and White sea level data, instead of Church’s 2009 data.  They also neglected a groundwater depletion correction.  When these improvements are included the VR2009 model yields 21st century sea level rises that are only about 55% of VR2009.  When the new GISS temperature data is included in the mix this drops to about 45%.

New GISS CW2009 Chao Wada

Case 3.

Lest Vermeer or Rahmstorf argue that their large sea level rise rates are saved by another update of the Church and White data in 2011, I have include these results also.  The difference between 2009 and 2011 Church and White sea level data was small.  Here is how the 2011 Church and White sea level data version plays out in the VR2009 model. The resulting 21st century sea level rise predictions are only about 43% of the VR2009 predictions.

New GISS CW2011 Chao Wada

The trend continues.

It seems that no matter what combination of inputs that are used in the VR2009 model, the predicted sea level rise for the 21st century is always smaller than with VR2009’s choice of inputs.  I wonder what that implies?


Seven IPCC Claims Refuted

December 8, 2014

Roger Andrews addresses seven claims of the IPCC Working Group 2.  I know that oil people are supposed to be automatically suspect, but open your mind and read what Andrews has to say as he handily addresses these points…

Claim 1: Glaciers continue to shrink almost worldwide due to climate change

Claim 2: Many terrestrial, freshwater, and marine species have shifted their geographic ranges ….. in response to ongoing climate change.

Claim 3: While only a few recent species extinctions have been attributed as yet to climate change, natural global climate change at rates slower than current anthropogenic climate change caused significant ecosystem shifts and species extinctions during the past millions of years.

Claim 4: Based on many studies covering a wide range of regions and crops, negative impacts of climate change on crop yields have been more common than positive impacts.

Claim 5: Impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones, and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability.

Claim 6: At present the worldwide burden of human ill-health from climate change is relatively small … and is not well quantified. However, there has been increased heat-related mortality and decreased cold-related mortality in some regions as a result of warming.

Claim 7: Violent conflict increases vulnerability to climate change.

Here is a teaser.

Part of Andrews’ responses for claims 1 and 4…

Glacier length

World Grain Production

Read Roger Andrews’ Latest IPCC Findings Undermine Climate Change Claims at


An easy climate change / energy quiz

November 13, 2008

Here is a simple, fun, 10 question quiz that covers a sample of climate change and/or energy issues.   Simply check the appropriate box and push the “vote” button for each question.  After you have pushed the vote button you will see the accumulated wisdom of everybody who has answered that question so far.  You can even leave a comment for any question, which I encourage.

Note that several of the questions requiring numerical answers have “order of magnitude” choices.   That is, they require “back of the envelope” type approximations, not high precision.

At the bottom of the quiz you will find a link to a solutions page, with links to supporting evidence, and “back of the envelope” calculations.  If you want, you can look at the solutions first and then take the quiz – but that would be cheating!

After enough people have answered the questions I will post the results at ClimateSanity.

Have fun!


 Here are five false color images of the sea ice in the arctic.  The images represent the ice on five year intervals on July 18th of 1988, 1993, 1998, 2003, and 2008.  Your task is to use your knowledge of changing conditions in the Arctic to put them in the proper chronological order.  Note that each image uses the same color scale (shown in the upper left corner of each image) to indicate the density of ice as a function of position. 

Image 1

Image 2

Image 3

Image 4

Image 5


Question 2


Question 3

In the fall of 2007, after the northern summer melt season, the Arctic sea ice extent anomaly reached its lowest level since satellite monitoring began in 1979.  This was followed by warnings that the Arctic ice could be completely gone by the summer of 2012. 


Question 4

In 1979 the worst nuclear accident in US history happened at Three Mile Island nuclear power plant near Middletown, Pennsylvania. 


Question 5

A rising sea level is one of the feared symptoms of global warming.  According to the Jason and Topax satellite tracking of ocean levels, the average sea level rise rate for the last 10 years has been about 3.2 mm per year.  This is interpreted by some to indicate an accelerating sea level rise rate.  IPCC expert Simon Holgate’s 2004 data (Holgate, S.J., and P.L. Woodworth, 2004: Evidence for enhanced coastal sea level rise during the 1990s. Geophys. Res. Lett., 31, L07305, doi:10.1029/2004GL019626.) was prominently featured in the IPCC’s Fourth Assessment Report (AR4, Working Group 1: The Physical Science Basis of Climate change, Chapter 5).  In a more recent 2007 paper (S.J. Holgate, “On decadal rates of sea level change during the twentieth century“, Geophysical Research Letters34: GL019626 (2007)., Holgate reconstructed sea level rise rates from high quality tidal gauge data going back to about 1900.


Question 6

NASA Scientist James Hansen estimated a sea level rise of 15 feet for the 21st century.


Question 7

The northern coast of Greenland is at 83.5 degrees north latitude.  It is the closest land to the North Pole.  Satellite data since 1979 has always shown this region locked in sea ice.  If global warming were to result in an ice free arctic sometime during this century, it is believed that this area would be the last place to lose its summer ice.


Question 8

Compact fluorescent light bulbs use only 25% of the energy of an incandescent light bulb to give the same number of lumens of light.


Question 9


Question 10

Since 1963 Africa’s Lake Chad has experienced severe shrinkage.  While atmospheric CO2 levels have continuously increased since 1963, the surface area of the lake has dropped from about 25,000 square kilometers to about 1,500 square kilometers.  This fact has been presented by Al Gore and others as a consequence of anthropogenically induced global warming.  Of course, this evidence must be considered in comparison to how the lake was changing when CO2 levels were not increasing. 


***Click here for quiz solutions***