OP3 - Oxidant and Particle Photochemical Processes above a Southeast Asian Tropical Rainforest

The OP3 project aims to quantify the emissions of trace gases from tropical forest, and study their contribution to the formation of oxidants and secondary particulate matter in a nearly undisturbed South-East Asian tropical environment. This will lead to better understanding of the impact of these processes on local, regional and global scale composition, chemistry and climate. Measurement campaigns will take place at the Danum Valley Field Centre in Sabah, Malaysian Borneo integrating ground-based, aircraft and satellite observations

Within OP3 the CEH Biogeochemistry Science Programme is combining its expertise in the measurement of biosphere/ atmosphere exchange processes with the air chemistry expertise of eight UK Universities (Lancaster, Manchester, Leicester, East Anglia, Cambridge, Leeds, York and Edinburgh).

CEH scientists contribute to OP3 through the measurement of emissions and deposition of biological particles, volatile organic compounds, nitrogen compounds (such as ammonia, nitrogen oxides and aerosol ammonium nitrate), greenhouse gases (methane, nitrous oxide, carbon dioxide) and ozone, both above and within the tree canopy.

The OP3 project is led by Professor Nick Hewitt (University of Lancaster) with 23 co-investigators from eight institutions including a team of CEH scientists. OP3 funded by a NERC Consortium Grant runs between 2007-2010, with measurement campaigns planned between spring and autumn of 2008. 

Why is OP3 needed?

Tropical forests account for over 50% of the World's forests (1.8 million ha) and act a massive source of matter and energy to the lower atmosphere.   Tropical ecosystems also account for almost half of global emissions of biogenic volatile organic compounds (VOCs), which play an important role in oxidant chemistry in the troposphere and subsequently climate. However the role of these VOCs in controlling chemical budgets and processes in the atmosphere is poorly understood.

The main aims of OP3 are to understand how emissions of reactive VOCs from a Southeast Asian tropical rainforest affect regional-scale production and processing of oxidants and particles in the troposphere, and to understand the impact of these processes on local, regional and global scales.

Latest information

The field campaign phase of the project consists of two separate ground-based measurement periods at the Danum Valley Research centre (7th April - 4th May 2008 and 21st June - 27th July 2008). The second of these campaigns will involve concurrent observations above the ground based site aboard the FAAM BAe 146 aircraft, a collaboration between the Met Office(TM) and the Natural Environment Research Council (NERC).

Links

CEH Biogeochemistry Programme.

OP3 Project website (external page).

Danun Valley Field Centre, Sabah (external page).

FAAM BAe 146 aircraft (external page).