I think this raises an interesting question. Do we continue to rely on science as the final court of appeal on this issue; it ain’t climate change until the scientists say it is? If so then we will forever be behind the curve of events; climate science, as a highly politicised endeavour, is innately cautious. If we don’t wait for science to tell us it’s climate change, then we are I suppose disputing perspectives on a playing field defined by values.

 

Though this is only a problem because of industrial lobbies deliberately engaging in campaigns to undermine what is obvious on the basis of reason – with atmospheric concentrations of CO2 at their highest level for half a million years, all weather is now an expression of a climate changed by anthropogenic activity.

 

From: Discussion list for the Crisis Forum [mailto:[log in to unmask]] On Behalf Of George Marshall
Sent: 17 February 2011 10:13
To: [log in to unmask]
Subject: Re: Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000

 

Here we have one of the central challenges of science communication. When an extreme weather event happens scientists are invited to make a connection with climate change. Quite understandably they are reluctant to do so without full research. This sometimes comes over as uncertainty- but increasingly I notice the formula “there is a difference between climate and weather- we cannot ascribe any single weather event to climate change” and this suggests that the extreme event is ‘natural variation’ not climate change...see for example the Met Office explanation of the cold winter which adamantly says that it is NOT ascribable to climate change

 

Then, years later, researchers collect sufficient evidence to establish a strong contribution in the event from climate change but this is too late and disconnected to help the public make the connection in their own minds.

 

What I find disturbing is that this pattern keeps happening (eg 2003 heatwave, Katrina, floods) and very likely will be repeated for the current record cold in Northern Europe and US. Science communications has not found a way of conveying this past experience- that, whilst it cannot be said with confidence without the research, previous extreme weather events have been found to be strongly influenced by climate change.

 

 

From: Discussion list for the Crisis Forum [mailto:[log in to unmask]] On Behalf Of Jon Barrett
Sent: 17 February 2011 07:23
To: [log in to unmask]
Subject: Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000

 

Dear all,

For those of us wanting to be able to communicate evidence of a clear, present and local CC threat, the Guardian reports today on this research just published in Nature

"Climate change doubled likelihood of devastating UK floods of 2000

Researchers have for the first time quantified the part climate change played in increasing the risk of a severe flood"

http://www.guardian.co.uk/environment/2011/feb/16/climate-change-risk-uk-floods

http://www.nature.com/nature/journal/v470/n7334/full/nature09762.html

Jon

Abstract from Nature 

Volume:470, Pages:382–385 Date published:(17 February 2011)

Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000

Interest in attributing the risk of damaging weather-related events to anthropogenic climate change is increasing1. Yet climate models used to study the attribution problem typically do not resolve the weather systems associated with damaging events2 such as the UK floods of October and November 2000. Occurring during the wettest autumn in England and Wales since records began in 17663, 4, these floods damaged nearly 10,000 properties across that region, disrupted services severely, and caused insured losses estimated at £1.3billion (refs 5, 6). Although the flooding was deemed a ‘wake-up call’ to the impacts of climate change at the time7, such claims are typically supported only by general thermodynamic arguments that suggest increased extreme precipitation under global warming, but fail8, 9 to account fully for the complex hydrometeorology4, 10 associated with flooding. Here we present a multi-step, physically based ‘probabilistic event attribution’ framework showing that it is very likely that global anthropogenic greenhouse gas emissions substantially increased the risk of flood occurrence in England and Wales in autumn 2000. Using publicly volunteered distributed computing11, 12, we generate several thousand seasonal-forecast-resolution climate model simulations of autumn 2000 weather, both under realistic conditions, and under conditions as they might have been had these greenhouse gas emissions and the resulting large-scale warming never occurred. Results are fed into a precipitation-runoff model that is used to simulate severe daily river runoff events in England and Wales (proxy indicators of flood events). The precise magnitude of the anthropogenic contribution remains uncertain, but in nine out of ten cases our model results indicate that twentieth-century anthropogenic greenhouse gas emissions increased the risk of floods occurring in England and Wales in autumn 2000 by more than 20%, and in two out of three cases by more than 90%.





--

Jon Barrett
Le projet pour une vie durable
Goastelliou
29620 Guimaec
France

Tel: 00 33 (0)2 98 67 68 87

 

Converging Crises blog: www.jontybarrett.wordpress.com

Goastelliou website: www.goastelliou.wordpress.com