Author: Alexandra Cheung

2°C or not 2°C – should we ditch the below 2°C target for global warming?

By Professor Joanna Haigh, Co-Director, Grantham Institute

A commentary published in Nature this week has opened up a discussion about the value of using the goal of keeping global warming to below 2°C.

David Victor and Charles Kennel are concerned that the below 2°C target for global warming is not useful, partly because they consider it is no longer achievable and partly because global mean surface temperature does not present a full picture of climate change.  The problem comes, of course, in identifying an alternative approach to establishing what is required from attempts to mitigate global warming.

The 2 degree target is in a sense nominal, in that it there is no precise threshold at which everything goes from bearable to unbearable, but it does have the advantage of being easy to understand, for both policy makers and the wider public .

Reflections on the UN Climate Summit in New York

By Dr Simon Buckle,  Grantham Institute

“Once more unto the breach, dear friends, once more”

Climate change was not, so far as I know, one of the issues that Shakespeare wrote about, despite plays like “The Tempest” or (for the sceptically minded) “Much Ado about Nothing”.  But King Henry V’s lines in Act III of the play of that name could have been written for the UN Secretary General to deliver at the Climate Summit in New York on 23 September where, with the help of a VIP cast, he in effect also urged us to “stiffen the sinews” to address one of the defining issues of our age.  

Feasibility and affordability of reducing greenhouse gas emissions

By Ajay Gambhir, Research fellow on mitigation policy at the Grantham Institute

The United Nations Climate Summit 2014, to be held in New York on 23rd September, comes at an important point in the calendar for discussions on how to address climate change. Next year will see nations submit pledges on their future greenhouse gas emissions levels, as part of the United Nations process culminating in the 21st Conference of the Parties (COP) in Paris at the end of 2015, the ambition of which is to secure a global agreement to tackle climate change.

There is now a rich body of evidence on the implications of mitigation at the global, regional and national levels.

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.

Merkel raises the level of ambition

By Dr Simon BuckleGrantham Institute

There was some good news last week from the annual Petersberg Climate Dialogues held on 14-15 July in Berlin.  The Petersberg meetings were instituted after the perceived failure of the Copenhagen summit in 2009 in order to support the UNFCCC talks. They are co-chaired by Germany and the country hosting the next Conference of the Parties meeting, in this case Peru.

Chancellor Merkel took the opportunity in her address to signal renewed ambition for climate action, perhaps disappointing some of those who had been hoping (or even working) for a reversal of Germany’s commitment to decarbonisation. 

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.

7 Frightening Findings from the IPCC Report

By Helena Wright, Research Postgraduate, Centre for Environmental Policy

Helena Wright, an Imperial PhD student, looks at worst possible scenarios from the IPCC Working Group II report.

The United Nations’ Intergovernmental Panel on Climate Change (IPCC) recently released its latest report, featuring the most up-to-date science on global climate change.

As a researcher, I had an opportunity to contribute to a table in one of the chapters and have read through each of the 30 chapters of the Working Group II report (on Impacts, Adaptation, and Vulnerability).  Here is my personal take on seven of the most frightening findings from the WG2 report:

  1. CO2 levels of 1000ppm could impact on mental performance

The health chapter explains how climate change will affect global health, including direct impacts of heat stress, drought and extreme events, as well as indirect impacts on nutrition and mental health.