Different Climate Computer Models by Gråulf

The only climate computer models we hear about are the ones used to predict global warming in the IPCC reports. The models are structured to prove a preconceived conviction, that the earth’s temperature is increasing and so is atmospheric CO2, so the increase in CO2 must be causing the increased temperature. Reasonable people might wonder why the interrelationship is not assumed to be the other way around, since ice cores all show that historically temperatures rose well ahead of CO2 levels, but then the phenomenon would not be our fault. None of the IPCC computer models can tell what the weather will be next week, but yet we are supposed to believe they can predict the weather a hundred years from now.

In fact, there are two fundamentally different ways in which computers can be used to project climate. The first is used by the modeling groups that provide the climate projections used by the IPCC. These groups deploy general circulation models, which use complex partial differential equations to describe the ocean-atmosphere climate system mathematically. The models used by the IPCC assume that CO2 is responsible for global warming, and that increased temperature will cause mostly positive feedback in the climate system. Never mind that if feedback loops were mostly positive the earth would have destroyed itself long ago. That suggest “garbage in, God’s truth out”.

Alternative computer projections of climate are constructed using data on past climate change, by identifying mathematical (often rhythmic) patterns within them and projecting these patterns into the future. Such models are statistical and empirical, and make no presumptions about complete understanding; instead, they seek to recognize and project into the future the climate patterns that exist in real world data.

In 2001, Russian geologist Sergey Kotov used the mathematics of chaos to analyze the atmospheric temperature record of the past 4000 years from a Greenland ice core. Based on the pattern he recognized in the data, Kotov extrapolated cooling from 2000 to about 2030, followed by warming to the end of the century and 300 years of cooling thereafter.

In 2003, Russian scientists Klyashtorin and Lyubushin analysed the global surface thermometer temperature record from 1860 to 2000, and identified a recurring 60-year cycle. This probably relates to the Pacific decadal oscillation, which can be caricatured as a large scale El Nino/La Nina climatic oscillation. The late 20th century warming represents the most recent warm half-cycle of the PDO, and it projects forwards as cooling of one-tenth of a degree or more to 2030.

In 2004, US scientist Craig Loehle used simple periodic models to analyze climate records over the past 1000 years of sea-surface temperature from a Caribbean marine core and cave air temperature from a South African stalactite. Without using data for the 20th century, six of his seven models showed a warming trend similar to that in the instrumental record over the past 150 years; and projecting forward the best fit model foreshadows cooling of between 0.7 and 1 degree Celsius during the next 20-40 years.

Most recently, Italian scientist Adriano Mazzarella demonstrated statistical links between solar magnetic activity, the length of the Earth day (LOD), and northern hemisphere wind and ocean temperature patterns. He too confirmed the existence of a 60-year climate cycle, and described various correlations (some negative). Based on these correlations, Mazzarella concludes that provided "the observed past correlation between LOD and sea-surface temperature continues in the future, the identified 60-year cycle provides a possible decline in sea-surface temperature starting from 2005, and recent climate data seem to support such a result".

As we see, there are other computer models. Scientists, using different mathematical techniques and many different data sets, arrive at conclusions very different from the IPCC models. Their conclusions are that CO2 does not drive global temperatures, and climate cooling will occur during the first decades of the twentieth century.

Gråulf.