It is about time this blog comes to the rescue of that little molecule called carbon dioxide. For the past millions of years it has helped trap heat in our atmosphere making life on earth possible but according to climate scientists mankind has been adding too much and now carbon dioxide is overheating the planet.
But it has never been easier being a global warming sceptic. This week a collection of email exchanges between global warming scientists were published that hackers had stolen from a university computer. From these exchanges a picture emerges that these scientists 1. may use statistical tricks in order to move data in the desired direction 2. may sweep data not fitting their models under the carpet and 3. may collude in smear campaign against scientists known to have a critical stand on climate change (see nytimes article).
And global temperature rise has come to a complete standstill anyway: for the past 10 years the planet has simply refused to heat up any further and global cooling is on the way. (see report in Der Spiegel or New Scientist). And how about those glaciers? The journal Science last week headlined No Sign Yet of Himalayan Meltdown, Indian Report Finds, the glaciers over there at least (contrary to many recent media reports) appear to be holding out despite global warming. According to climate scientist John Shroder cited in the Science article :The bottom line is that IPCC's Himalaya assessment got it horribly wrong (..) They were too quick to jump to conclusions on too little data. (DOI).
And how about those sunspots!. Solar activity varies over time and low activity as evidenced by low sunspot count corresponds to a relatively cool climate. The Little Ice Age in the 17 Th century is attributed to an extended solar slumber. Yet according to the IPPC (2007) solar activity today only accounts for 10% in the overall global warming. Nevertheless it is very tempting to connect the current global warming pause with the recent phenomenon of the missing sunspots. In a July 2009 article the NYTimes cites a NASA scientist on solar activity stating that it's been as dead as a doornail and in the beginning of 2009 there was a long lull of several months of virtually no activity, which had me worried (sunspot numbers here). The next solar maximum in 2013 is predicted to be the weakest since 1928.
But do not underestimate the IPPC. In their 2007 synthesis report they do not only assess radiative forcing components but also add an assessed level of scientific understanding (LOSU) for each component. And for carbon dioxide the LOSU value is high but for solar irradiance LOSU is low. So it is still possible for carbon dioxide to have it's name cleared if it is possible to steer research in the right direction although not before the upcoming Copenhagen 2009 summit.