This is a call for some very easy help with my first video project – a short clip on the difference between weather and climate, approximately. (The exact content isn’t fixed yet.) More background below.

I have created a corresponding vimeo project, and posted a link to this description on causes.com: Stop Global Warming.
If you are interested in participating, you can reply either here (comment below or send me an email), or at any of the above links.

I am looking for a couple of brief and simple contributions to a small project; as I will explain below, these could be very short (seconds…) videos, or they could be similarly brief ‘interviews’ via video chat which you’d be allowing me to record. Of course, there is also the hybrid possibility: we chat via voice chat, but record ourselves with independent cameras (quality-wise presumably the best solution, but I’m not looking to make things terribly complicated).

What I would like to compile are instantaneous weather ‘observations’ from worldwide locations – as disparate from each other as possible. Most importantly temperature, but also what the sky looks like, precipitation (if any), and if there is any precipitation on the ground (i.e. snow).

The only requirement is that all of the observations should be performed approximately simultaneously across the globe. Once a couple of people have indicated their interest in participating, we can determine a time together that suits as many of us as possible. I will, in general, also want a geolocation of the observation, e.g. from Google Maps.

What is this for? I have a couple of ideas for short clips on issues connected to climate change, resource use and similar topics. I have no experience with shooting videos so far (though plenty with photography), so this is going to be my initiation . I am a climate scientist though, and my intention is to learn to communicate issues that I deem important to a broader public.

The first clip I have in mind – the one I am soliciting your help with here – is about the difference between instantaneous weather and global averages. Or, “why this cold winter doesn’t mean that global warming isn’t happening”. Your contributions from all corners of the globe are meant to illustrate the fact that at any instance in time, there are all kinds of different ‘weathers’ going on in different places. (If this is successful, an extension to averages in time might be a nice extension.)

The only claim pertaining to an actual scientific investigation is that of manipulating or hiding data, and the relevant quote from one of the emails is:

“I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie, from 1981 onwards) and from 1961 for Keith’s to hide the decline.”

Let me explain: There are two fundamentally different types of data that can be used to study climatic trends. Type one are direct instrumental measurements, of which we have tons for recent times, but going back further in time (say, more than one or two centuries), they get sparse. Direct measurements leave no doubt whatsoever about the occurrence of recent global warming.

Type two are indirect data (we call them proxy data or climate reconstructions). Here, a physical quantity that is affected in some way by temperature and preserved in some sort of long-lasting record is measured. Examples include ocean sediments, layers of ice in polar ice caps and other glaciers, or the now-infamous tree rings (and many more). As the term ‘reconstruction’ already implies, the relationships between temperatures and the measured physical quantities are not always straightforward, and methods are not always foolproof (but subject to constant improvements). Having said that, some of these indirect climate reconstructions are more reliable than others, but scientists do not underplay these uncertainties in publications such as the IPCC reports.

“Decline”: The decline in the email excerpt refers to the apparent decline in temperatures reconstructed from tree rings. Not measured temperatures. The latter clearly show global warming. So why use tree rings at all? Apparently, the discordance between tree-ring-reconstructed and measured temperatures only affects the time after about 1960. The reasons for this are, I believe, not known (but this is irrelevant for this discussion). Before c. 1960, tree-ring and measured temperatures are in agreement, which is why tree-ring data are occasionally used to corroborate data from earlier time periods, for which not as many instrumental measurements are available.

“Trick”: The trick here refers to a way of overcoming the known issue of the unreliability of tree ring reconstructions after c. 1960, namely by replacing them by instrumentally measured, and hence intrinsically more reliable, data. The email is claimed to refer to the preparation of a graph for the cover of the WMO statement on the status of the global climate in 1999. (This can’t be deduced from the email in question, though.) I followed up the references in the graph, and it turns out that only part of the data are from tree rings at all.

The graph of discontent on the title of WMO statement

As to the rest of the usually quoted emails, they have little to do with science and I will leave commenting on them for another time.