Dr. Ole Humlum
Dr. Ole Humlum, Professor of Geosciences at the University of Oslo. PhD in Glacial Geomorphology [a combination of geography/geology] [Uni Copenhagen]
Ole Humlum has become the deniers expert for – CO2 increases are natural, and increased temperatures are just natural variations. Deniers may also cite that the last inter-glacial period was warmer, and that we are following a similar trend [which will ultimately lead to another ice age]. The message is don’t worry, it’s natural, the increased CO2 comes from the oceans, and humanity can carry on burning fossil fuels.
A full argument of Ole Humlum’s views can be found here at The Hockeyshtick blog.
Dr. Ole Humlum, Professor of Geosciences at the University of Oslo, has published a summary and reply to comments on his groundbreaking paper demonstrating why man-made CO2 is not the driver of global warming. Dr. Humlum summarizes the main findings of his paper at a Norwegian website for geologists:1. [Observations show] The temperature rise begins at sea level and spreads gradually to the land and atmosphere several months later. This is contrary to the IPCC CO2 hypothesis that atmospheric CO2 controls land and ocean temperature.2. The geographical distribution of a CO2 increase doesn’t start at 30-50 degrees North latitude, which one would expect if the source were mainly created by the fossil fuel industry and transport in the Northern Hemisphere. Instead, the increase of CO2 starts just south of the equator. This is contrary to the IPCC hypothesis that use of fossil fuels is the primary cause of increased CO2 levels.Dr. Humlum notes that existing climate models are based on the improper assumption that CO2 controls temperature and have not provided skillful predictions so far. He concludes,
“One should therefore consider moving the focus of climate research from CO2 to the nature and significance of natural variation, both related to the sun and other [natural causes]. It is most likely where we will find the main reason for the present (and future) climate change.”
The signature graph frequently reposted is below.
making it look like this [the Greenland temperature is 2c greater]
and with a correction to the CO2 levels looking like this
Ole Humlum runs the blog Climate4you which mixes climate data from a number of sources with his own graphs.
As for CO2 increases being natural - information is available here. Text from NOAA Earth System Research Laboratory.
How do we know that humans are responsible?
The evidence for a dominating human role in the CO2 increase is extremely strong. The 38% increase (in 2009) in atmospheric CO2 observed since pre-industrial times cannot be explained by natural causes. CO2 levels in the atmosphere have varied naturally throughout Earth’s history. However, CO2 levels are now higher than any seen in the past 800,000 years. When we add the observed CO2 increase in the atmosphere to the observed increase in the oceans, the sum is approximately equal to all of the coal, oil, and natural gas burned since the 19th century. Furthermore, the observed progressive depletion in carbon-13 (see the question below about isotopes) shows that the source of the CO2 is either fossil fuels or deforestation because both produce CO2 depleted in carbon-13. The atmospheric CO2 increase cannot have come from the oceans because that would not have caused any depletion of carbon-13. In fact, carbon in the oceans has itself become gradually depleted in carbon-13, with the greatest depletion at the surface. That implies that the signal is imposed from the atmosphere. The next piece of evidence is that we also observe a depletion of radioactive carbon-14 in the atmosphere and oceans, with the strongest signal in the atmosphere suggesting it is the place where the depletion originates. Fossil fuels contain no carbon-14, and their combustion produces CO2 without carbon-14. Deforestation does not cause a change in atmospheric carbon-14. Finally, the annual mean CO2 abundance in the northern hemisphere is higher than in the southern hemisphere, and more so in recent years compared to the early years of atmospheric CO2 measurements. This suggests a growing source of CO2 in the northern hemisphere, which is in fact where most of the fossil fuel burning takes place.