Nova’s Dryspot

Recent research by Fasullo and Trenberth (covered here by SkS) showed that climate models that do a better job at reproducing observations of humidity, are also forecasting a higher sensitivity (greater warming).

Models that better simulate humidity near the infamous hotspot that Nova harps on about, suggest that the warming will be at the higher end of current estimates.

Joanne Nova wants nothing more than to discredit the models, and finds opportunity in John Christy’s blog post. Yeah it’s not peer-reviewed science, of course, but let’s take a look anyway at Christy’s folly.

John Christy claims the models that get closer to the observations, are the ones that don’t get closer to observations. Yeah, I agree, something’s not right! Christy’s measure for whether a model is correct ornot, is done by cherry picking.

Christy cherry picks a starting year of 1998 (number one sign of someone in climate denial) because this year was influenced by an intensely strong El Nino that has the effect of enhancing the surface temperature on a short term basis. Since 1998 we’ve had much weaker ENSO states with a higher incidence of La Nina conditions that have produce cooler temperatures.

Christy also cherry picks the source of data, RSS, because it’s most affected by the ENSO cycle in 1998 and the only one showing cooling since that cherry picked year.

4 Majors data sources - Christy picks one

4 Majors data sources – Christy picks one

As mentioned earlier, making comparisons between Models and Observations produces better results when the natural variations and influences that cannot be modelled are accounted for.

Observed annual global temperature, unadjusted (pink) and adjusted for short-term variations due to solar variability, volcanoes and ENSO (red) compared to the scenarios of the IPCC (blue range and lines from the third assessment, green from the fourth assessment report).

Observed annual global temperature, unadjusted (pink) and adjusted for short-term variations due to solar variability, volcanoes and ENSO (red) compared to the scenarios of the IPCC (blue range and lines from the third assessment, green from the fourth assessment report).

Christy and Nova fail to do this. By cherry picking the year and the data, they wrongly claim the models that get it right are the ones getting it wrong.

Advertisements

Tags: , ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: