Why not use a clever mathematical trick?

RealClimate - There is a clever mathematical trick for comparing different data sets, but it does not seem to be widely used. It is based on so-called empirical orthogonal functions (EOFs), which Edward Lorenz described in a Massachusetts Institute of Technology (MIT) scientific report from 1956. The EOFs are similar to principal component analysis (PCA). The EOFs and PCAs provide patterns of spatio-temporal covariance structure. Usually these techniques are applied to datasets with many … [Read more...]

Why are so many solar-climate papers flawed?

RealClimate - The Zharkova et al paper that incorrectly purported to link solar-climate effects to movements of the Sun around the barycenter has been retracted. This paper generated an enormous thread on @PubPeer where the authors continued to defend the indefensible and even added in new errors (such as a claim that the Earth’s seasonal cycles are due to variations in the Earth-Sun distance). Additionally, it seeded multiple nonsense newspaper articles in the UK and elsewhere (some … [Read more...]

Further perspectives on pandemics and climate change

RealClimate - I have recently been asked whether the present corona pandemic will have any consequence on climate change. Gavin has already discussed the coronavirus and climate here on RealClimate, and I like to follow up on his post. Rather than emphasising analogies, I would highlight additional common denominators between the present world-wide Covid-19 pandemic and climate change. My first reaction is that the present crisis has taught us the value of knowledge and science. It is also … [Read more...]

Coronavirus and climate

RealClimate - As we collectively reel from the changes wrought by the current pandemic, people are being drawn by analogy to climate issues – but analogies can be tricky and often distort as much as they illuminate. For instance, in the Boston Globe, Jeff Jacoby’s commentary was not particularly insightful and misquoted Mike Mann pretty egregiously. Mike’s response is good: I am relieved to see policy makers treating the coronavirus threat with the urgency it … [Read more...]

Exploring CRUTEM4 with Google Earth

RealClimate - Guest commentary by Tim Osborn and Phil Jones The Climatic Research Unit (CRU) land surface air temperature data set, CRUTEM4, can now be explored using Google Earth. Access is via this portal together with instructions for using it (though it is quite intuitive). We have published a short paper in Earth System Science Data (Osborn and Jones, 2014) to describe this new approach. This is part of ongoing efforts to make our climate data as accessible and transparent as … [Read more...]

Going with the wind

RealClimate - A new paper in Nature Climate Change out this week by England and others joins a number of other recent papers seeking to understand the climate dynamics that have led to the so-called “slowdown” in global warming. As we and others have pointed out previously (e.g. here), the fact that global average temperatures can deviate for a decade or longer from the long term trend comes as no surprise. Moreover, it’s not even clear that the deviation has been as large as is … [Read more...]

Can we make better graphs of global temperature history?

RealClimate - I’m writing this post to see if our audience can help out with a challenge: Can we collectively produce some coherent, properly referenced, open-source, scalable graphics of global temperature history that will be accessible and clear enough that we can effectively out-compete the myriad inaccurate and misleading pictures that continually do the rounds on social media? Bad graphs One of the most common fallacies in climate is the notion that, because the climate was hotter … [Read more...]

The Nenana Ice Classic and climate

RealClimate - I am always interested in non-traditional data sets that can shed some light on climate changes. Ones that I’ve discussed previously are the frequency of closing of the Thames Barrier and the number of vineyards in England. With the exceptional warmth in Alaska last month (which of course was coupled with colder temperatures elsewhere), I was reminded of another one, the Nenana Ice Classic. For those that don’t know what the ‘Classic’ is, it is lottery … [Read more...]

New daily temperature dataset from Berkeley

RealClimate - Guest commentary from Zeke Hausfather and Robert Rohde Daily temperature data is an important tool to help measure changes in extremes like heat waves and cold spells. To date, only raw quality controlled (but not homogenized) daily temperature data has been available through GHCN-Daily and similar sources. Using this data is problematic when looking at long-term trends, as localized biases like station moves, time of observation changes, and instrument changes can introduce … [Read more...]