Category: Climate scepticism

With climate models, simpler isn’t necessarily better

Grantham Institute Co-Director Professor Joanna Haigh discusses a recent paper which argues that  existing climate models ‘run hot’ and overstate the extent of manmade climate change.

It is perplexing that some climate change sceptics, who expend much energy in decrying global circulation (computer) models of the climate, on the basis that they cannot properly represent the entire complexities of the climate system and/or that they contain too many approximations, are now resorting to an extremely simplified model to support their arguments.

The model used in the Sci. Bull. article is a very useful tool for conceptualising the factors which contribute to the relationship between increasing concentrations of carbon dioxide in the atmosphere and global average temperature – indeed, we use such models as teaching aids for students studying atmospheric physics – but it is in no way fit for purpose as an accurate predictor of climate change.  

In defence of biomass energy

By Professor Colin Prentice, AXA Chair in Biosphere and Climate Impacts

Further to previous posts on this blog regarding Owen Paterson’s recent speech to the Global Warming Policy Foundation, I would like to take this opportunity to correct his dismissive statement about biomass energy as a potential contribution to decarbonized energy production in the UK. This is what the former Environment Secretary said:

Biomass is not zero carbon. It generates more CO2 per unit of energy even than coal. Even DECC admits that importing wood pellets from North America to turn into hugely expensive electricity here makes no sense if only because a good proportion of those pellets are coming from whole trees.

Has climate change been exaggerated? Fact-checking Owen Paterson’s comments

By Dr Flora WhitmarshGrantham Institute

In a lecture to the Global Warming Policy Foundation, the former UK Environment Secretary Owen Paterson has criticised the current government’s climate and energy policies, suggesting there is too much emphasis on renewables and that the consequences of climate change have been exaggerated. A discussion of Mr Paterson’s comments on UK energy policy appears in another Grantham blog by Dr Simon Buckle. Here I will discuss one of the reasons for Paterson’s position, the belief that climate change has been exaggerated.

Paterson suggested that the Earth has not warmed as much as had been predicted, “ … I also accept the unambiguous failure of the atmosphere to warm anything like as fast as predicted by the vast majority of climate models over the past 35 years, when measured by both satellites and surface thermometers.

Paterson misses the point

By Dr Simon Buckle,  Grantham Institute

Owen Paterson’s remarks on the UK response to climate change miss the point.  I do not disagree with him that the UK decarbonisation strategy should be improved.  In particular, there is a need for a more effective strategy on energy demand.  However, my preferred policy and technology mix would be very different to his and include the acceleration and expansion of the CCS commercial demonstration programme in order to reduce the energy penalty and overall costs of CCS. And without CCS, there is no way responsibly to use the shale gas he wants the UK to produce in the coming decades for electricity generation or in industrial processes, or any other fossil fuels.

Ocean heat uptake – checking the facts

The Climate and Environment at Imperial blog has moved. View this post on our new blog 

By Dr Flora Whitmarsh, Grantham Institute

The recent slowdown in global temperature rise has led to suggestions that global warming has stopped. In fact, the Earth system is still gaining heat, and the slowdown was likely caused by a series of small volcanic eruptions, a downward trend in the solar cycle, and increased heat uptake of the ocean. Writing in the Telegraph, Christopher Booker claims that a new paper by Professor Carl Wunsch (Wunsch, 2014) shows that ocean warming cannot explain the slowdown because the deeper ocean is in fact cooling rather than warming.

Ocean warming in the media

A recent paper on ocean warming has been reported on in a number of newspaper articles, most recently by Christopher Booker in the Sunday Telegraph.

The author of the paper, Professor Carl Wunsch of MIT, wrote a letter to the editor of the Sunday Telegraph in response to Christopher Booker’s article. As the letter has yet to be published in the Sunday Telegraph, with the permission of Professor Wunsch we have decided to post it here.

Dear Editor,

In the Sunday Telegraph of 27 July 2014, Christopher Booker pretends to understand a highly technical paper on ocean warming to such a degree that he can explain it to his lay-audience.

Fact checking a recent Telegraph article by Christopher Booker

by Dr Flora WhitmarshGrantham Institute

In an article for the Telegraph, Christopher Booker gave his views on Professor Sir Brian Hoskins’ appearance on the Today programme earlier this year. In the article, Booker made several claims about climate science relating to rainfall, atmospheric humidity, polar sea ice extent, global temperatures and sea level rise. In this blog I will assess his claims against the findings of the latest report of Working Group 1 of the Intergovernmental Panel on Climate Change (IPCC), a hugely comprehensive assessment of the scientific literature.

  Rainfall and floods

Booker’s comment: “Not even the latest technical report from the UN’s Intergovernmental Panel on Climate Change (IPCC) could find any evidence that rainfall and floods were increasing.”

 Scientific Evidence:

The IPCC report found a significant climate influence on global scale changes in precipitation patterns (with medium confidence), including increases in precipitation in northern hemisphere mid to high latitudes.

Science and an open society

By Dr Simon Buckle, Grantham Institute

Professor Lennart Bengtsson’s resignation from the GWPF (Global Warming Policy Foundation) Academic Advisory Council has received wide coverage and raises important issues.

Whatever anyone’s views are on the role, motivation and integrity of the GWPF in this matter, it is up to individual academics whether or not to associate themselves with it in an advisory role.

It is regrettable that perceived political stances on the climate issue are apparently so affecting academic activity.  The Grantham Institute at Imperial has always opposed such behaviour, believing that scientific progress requires an open society.  We try to engage with a wide range of figures, some with radically different views on climate change.

Question Time and what the IPCC really said about tropical storms

By Dr Simon Buckle

BBC’s Question Time on 14 November saw Lord Lawson citing the IPCC findings to support one of his arguments.  Did I dream that? Then I realised that, of course, the reference to the IPCC was incomplete and misleading so I knew I was awake and back in the strange media-distorted world of the UK debate on climate change.

According to the Daily Express, Lord Lawson said that “If you look at the inter-governmental panel on climate change they say there is absolutely no connection between climate change and tropical storms.” Wrong, but convenient for someone who argues we probably don’t need to do anything much about climate change.

Transient Climate Response: an incomplete measure of climate change

By Dr Simon Buckle

It may help to clarify some of the facts related to the lively exchange between Bob Ward and Lord Ridley about the Transient Climate Response (TCR). The TCR is defined by the IPCC as “the change in the global mean surface temperature, averaged over a 20-year period, centred at the time of atmospheric carbon dioxide doubling, in a climate model simulation in which CO2 increases at 1% yr – 1.”

Lord Ridley is right that the IPCC in its recently published AR5 Working Group I report gave an estimated likely (66–100% probability) range for TCR of 1 – 2.5°C.