Archive for the ‘Sherwood Idso’ Category

Nova’s Warm Period

September 3, 2012

The Medieval Warm Period (MWP) is defined the time as between AD 950 to 1250 where evidence shows that some parts of the planet were warmer than average.

Nova claims that her friends at the denialist, Exxon funded website CO2Science have demonstrated that the MWP was globally warmer in the past, without CO2.

  • Firstly, SO WHAT? We know it was certainly warmer sometime in the past. What matters today is that we are causing it, at a very rapid rate and the science says we are going to heat up well beyond what the MWP might have been.
  • Secondly, if were warmer n the MWP than today, then this is evidence for a high sensitivity value, something climate denialists don’t want.
  • Thirdly, CO2Science don’t perform science, they draw their own conclusions from other peoples science. The Co2Science analysis is not peer-reviewed, contains some serious flaws and it would appear they deliberately aim to deceive their readers.

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Climate Sensitivity – Idso? Idsnot!

April 2, 2012

Climate sensitivity is defined as

a measure of how responsive the temperature of the climate system is to a change in the radiative forcing.

Nova’s recent claim on this topic is the use of Sherwood Idso’s research from the 1980’s. Idso’s research was scientifically debunked because his calculation did not actually equate to that of climate sensitivity (see below). No climate scientist used Idso’s methods to determine climate sensitivity because, as we’ll examine, his mistakes were obvious, measuring the change in surface radiation rather than top of atmosphere, measuring the changes in one small location, then extrapolating that to the whole planet, measuring apparent changes in Mars and expecting the Earth to respond in a similar way, not allowing time for equilibrium to be reached.

The most obvious reason why Idso’s estimate of 0.4°C rise in temps for a doubling of CO2 is too low; the planet has warmed that much since he first published in 1984, whilst CO2 levels rose 15% from 350 to 390 ppm.

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