The mix of site locations in the Equianos Network, analysis methods at Royal Holloway for bag and flask sampling and back trajectory analysis allows focus on both sources of Arctic greenhouse gases and also work determining changes in tropical greenhouse emissions and sources.
Methane emissions (roughly around 500 Tg/yr) are both natural and anthropogenic. Fluxes remain very poorly quantified, especially as they may vary greatly for year to year. Most natural emissions (around 200 Tg/yr, varying significantly from year to year) respond rapidly to climate change, including anthropogenically generated change. Tropical methane sources emit perhaps two-fifths of the global methane budget and tropical hydrology is potentially very vulnerable to global climate change. The current problem is that to quote Bousquet et al. (2006) “The sparseness of the tropical network….prevents us from verifying..” The sparseness of the tropical monitoring network is shown below in an equal area projection courtesy of Andrew Manning, UEA.
By having continuous measurement stations, and co ordinated bag/flask sampling around the South Atlantic rim, and also on the mobile platform the James Clark Ross, the Equianos network is hoped to give a coordinated picture of the South Atlantic system as well as increasing the scope of the tropical methane measurement network.
Currently, the Greenhouse gas group are working on using 13C isotopes from CH4 to determine likely sources of methane whilst also looking at trends in concentrations of greenhouse gas emissions (especially the rate of increase of methane in tropical and Southern hemisphere regions).
Data from the Equianos network is anticipated to be graphically displayed on this site on a monthly basis soon from selected sites, detailed requests for data must be made to the group leader.