International Greenhouse gas experts meet in Wellington

World experts on greenhouse gases will get together at the 16th WMO/ /IAEA meeting on Carbon Dioxide, other Greenhouse Gases, and Related Measurement Techniques (GGMT) conference, from 25-28 October 2011, in Wellington.

NIWA conference organiser Gordon Brailsford says a key aim of the meeting is to refine measurement methodologies and make them more consistent, as precise measurements of greenhouse gases need to be made, and data sets compared, to get an accurate picture of the global situation. In recent years, there has been much discussion, and concern, about the rates at which greenhouse gas levels in the atmosphere are rising.

Dr Pieter Tans of the Earth System Research laboratory (NOAA) is a plenary speaker at the conference. His public talk at Victoria University of Wellington is on "Climate change and the end of exponential growth". Since 1985, he has led the Carbon Cycle Greenhouse Gases group at NOAA. He discovered the very large 'sink' uptake of CO2 by terrestrial ecosystems at mid-latitudes in the Northern Hemisphere.

Other international representatives include Oksana Tarasova, from the World Meteorological Organization Research Department in Switzerland. Her speech is on "Greenhouse gas observations and analysis in the WMO/GAW Programme".

Prof Martin Manning from the New Zealand Climate Change Research Institute is a plenary speaker and will talk on "Global risk management". "We are increasing the pressure on our environment the whole time," he says. His concern is that the atmospheric concentrations of CO2 are rising at an increasing rate, and there is already a commitment to a very different climate for several thousand years into the future.

Currently, countries report on their own level of gas emissions. This can lead to underestimation. "It's not enough to leave it up to the governments to say how much gas is going into the atmosphere," says Prof Manning. "There is an increasing role for scientists to track the sources as well as the extent to which they are being removed by natural processes."

A highlight of the meeting is a field trip to NIWA's world-renowned atmospheric monitoring station at Baring Head, on 24 October. Baring Head is an important part of the WMO Global Atmospheric Watch network. New Zealand started making measurements of CO2 in 1972, when atmospheric CO2 concentrations were 323 parts per million.

There is now about 20% more in the atmosphere. Key greenhouses gases, including methane and nitrous oxide, are measured at the station and significant changes are tracked. Baring Head Clean Air Station is exposed to strong southerly winds that have not been in contact with land for at least five days. NIWA monitors the composition of air at Baring Head because it is representative of large areas of the mid-latitude Southern Hemisphere.

Methane is now increasing faster in the Southern Hemisphere. "We could be approaching a threshold for methane which will have major ramifications," says Prof Manning.

NIWA is the host institute for this conference. For more details see the main conference page.


WMO - World Meteorological Organization IAEA – International Atomic Energy Agency See this chart of Global CO2 on the US Earth System Research Laboratory's website.

NIWA's atmospheric monitoring station at Baring Head. (Dave Allen)
Atmospheric Methane measured at Baring Head