I realise Sou has already covered this but, since I haven’t done a Watt about post for some time, I thought I would also comment. The post I’ll be discussing is a guest post on Watts Up With That (WUWT) by David Whitehouse, who is an Academic Advisor to the Global Warming Policy Foundation and who also happens to have a Ph.D. in astrophysics.
Before I discuss his guest post, I’ll point out that he recently suggested that
Remember when some analysts used 1998 as a start point for global temperature trend analysis they were rightly criticised for it. It now seems that some are using a strong El Nino year – 2015 – as the endpoint for their analysis!
while failing to mention his report from 2014, which starts with
What is the reason for the lack of warming observed at the surface of the Earth since about 1997?
Not only is this somewhat ironic, I don’t think that including the most recent data point in your analysis would typically regarded as a cherry-pick; it’s not as if we’re simply choosing to not use the data for the future.
Now back to his WUWT guest post (archived here). In this post, David Whitehouse claims that, with respect to 2015 being the warmest year on record, some scientists deliberately mistook weather for climate. His argument is essentially that
the large increase over 2014 is far too great and swift to be due to a resurgence of forced global warming. It must be due to short-term natural variability, and you don’t have to look far to find it. 2015 was the year of the El Nino which boosted the year’s temperature.
Not only is this silly (does he really think that forced warming somehow stopped, rather than simply being masked by variability?) but it would probably still have been a record year even without the El Nino:
What about the impact of El Niño on the 2015 record? It gave an assist – but record would have been broken anyway pic.twitter.com/BXFOQQUWbE
— Gavin Schmidt (@ClimateOfGavin) January 21, 2016
Even though 2015 is only a single year, it is still the warmest in a record going back more than 100 years; is warmer than previous El Nino years, and – what is more – in the past decade we’ve had La Nina years that are warmer than previous El Nino years. There is a clear warming trend, that indicates that we continue to warm, largely because of our emissions of greenhouse gases.
David Whitehouse then goes on to say
The IPCC says that just over half of the warming since the fifties is forced so most of the contribution to 2015′s temperature is natural variability.
Well, this is utter nonsense. What the IPCC actually says is
It is extremely likely that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas concentrations and other anthropogenic forcings together.
Surely even David Whitehouse understands that more than half is not the same as just over half, especially as it goes on to say
The best estimate of the human-induced contribution to warming is similar to the observed warming over this period.
In other words, anthropogenic influences probably contributed to most of the observed warming since 1950, possibly even more than all of it.
Given that David Whitehouse has a PhD in astrophysics, it’s really hard to understand how he can’t get this basic point. It’s almost as if he deliberately mistook just over half for more than half. You might think that someone with his credentials would be willing to correct such a mis-representation. However, given that he seems to think WUWT is a site worth posting on, I’d be very surprised if he did.