September 9, 2014

expert reaction to the World Meteorological Organization’s Greenhouse Gas Bulletin

The World Meteorological Organization reported that the volumes of atmospheric greenhouse gases rose to the highest levels, and at the fastest rate since accurate recording began.

Prof Martin Siegert, Professor of Geosciences at the University of Bristol, said:

“We’re at CO2 conditions not seen since the Pliocene, 3.5 million years ago. If we’ve now set the atmospheric ‘oven temperature’ to that time, we will see sea level rise of over 20m. This may take several centuries, if not millennia, but the change will be profound and is likely irreversible without a concerted effort to take carbon from the atmosphere now and over the coming decades.”

Prof Richard Allan, Professor of Climate Science at the University of Reading, said:

“The increase in global atmospheric CO2 concentrations from 2012 to 2013 was the largest year to year change in the World Meteorological Office record going back to 1983, although was similar to the 1997 to 1998 increase.

“A more important message from the report, however, is that the continued increase in CO2, primarily due to the combustion of fossil fuels, is contributing over 80% of the increased heating affecting the planet over the past decade.

“Increases in atmospheric CO2 would be more than double were it not for the land surface and oceans absorbing in approximately equal measure the additional human caused CO2 emissions. Uptake by the sea surface is already making the oceans steadily less alkaline (more acidic) which is of concern for the health of crucial marine organisms.

“A pause in the rise in atmospheric methane concentrations in the early 2000s has given way to a continued increase since 2006, adding to the heating effect of CO2.  Both natural sources and emissions from human activities such as agriculture, landfill and burning of fuels are contributing to this variation in methane.

“Substantial reductions in CO2 emissions are required to stabilise the increasing heating effects from rising atmospheric concentrations thereby avoiding the most substantial and dangerous climate change scenarios.”

Prof Dave Reay, Chair in Carbon Management at the University of Edinburgh, said:

“That carbon dioxide concentrations continued to surge upwards last year is worrying news. This is the litmus test when it comes to our efforts to reduce emissions and on this evidence we are failing. Of particular concern is the indication that carbon storage in the world’s forests and oceans may be faltering. So far these ‘carbon sinks’ have been locking away almost half of all the carbon dioxide we emit. If they begin to fail in the face of further warming then our chances of avoiding dangerous climate change become very slim indeed.”

Prof Joanna Haigh, Co-Director of the Grantham Institute for Climate Change and Environment, Imperial College London, said:

“These measurements show the unremitting increase of carbon dioxide in the atmosphere. Indeed, far from a slowdown, the concentration is rising faster than ever – with an inevitable impact on future global temperatures. To have any chance of avoiding increasingly serious impacts of climate change steps need to be taken now to reduce CO2 emissions.”

Prof William Collins, Prof of Meteorology at the University of Reading, said:

“Greenhouse gases continue to rise, adding another 0.08W/m2 of radiative forcing on top of the values reported in the latest IPCC Assessment.

“Detailed analysis of the isotopic composition in this report shows that more than half of the man-made CO2 emissions over the last 10 years have been removed from the atmosphere; but we can’t expect to benefit from this natural removal for ever.  The report suggests that the biosphere may be removing less CO2 as the climate warms, and that the warming may also be increasing natural emissions of methane. This is consistent with our understanding of biogeochemical processes and would imply a future amplification of climate change.”

Declared interests

None declared