The Laboratory for Global Marine and Atmospheric Chemistry (LGMAC) was created in 2001 with funding from NERC under the JIF scheme of £7million pounds for the creation of new and improved laboratory facilities and equipment.
Specialist facilities developed include laboratories for culturing marine algae, handling ice cores and ulta-clean facilities for the analysis of trace metals and new equipment included state-of-the-art analytical equipment for the measurement of gases, aerosols and dissolved material in the ocean and their isotopic composition.
The research of LGMAC centres on understanding the way the atmosphere and oceans interact to regulate climate. The research therefore includes both marine and atmospheric chemists working in uniquely close collaboration. The work is focussed on the marine boundary layer and the upper layers of the ocean, although many of the researchers in LGMAC also work outside these particular boundaries.
The LGMAC research is directly relevant to a wide range of important current scientific issues of very direct societal concern. Here are just a few examples.
- We study the air-sea exchange of carbon dioxide, the key greenhouse gas and the role of biological and physical processes in the ocean in controlling this.
- We study the cycling of halogens (chlorine, bromine and iodine) between the ocean and the atmosphere and the role of these exchanges in controlling ozone cycling in the atmosphere. This work includes studies of chlorofluorocarbons (CFCs) and their replacement compounds which are known to be the cause of the "ozonehole".
- We study the exchange of a variety of trace gases from the ocean which react in the atmosphere to form aerosols which reflect sunlight back to space and thereby influence climate.
- We study the chemistry of aerosols in the atmosphere and their role in transporting key nutrients to the oceans which influence ocean primary productivity. It has been argued that changes in desert dust transport and the associated supply of iron altered ocean productivity sufficiently to contribute to the last ice age.
The work of LGMAC includes laboratory analyses and modelling as well as a major component of field work. Over the last 5 years LGMAC researchers have covered the globe from the Antarctic to the high Arctic from Hawaii and Australia to North Africa. This work involves sampling from aircraft such as the new NERC research aircraft and ships such as the NERC research ship James Clark Ross.
Researchers from LGMAC turn these platforms into sophisticated analytical laboratories able to make some of the most detailed measurements possible. Such field work is demanding in many ways but essential since many of the key chemical species we need to measure cannot be collected and stored for analysis.
The Weyborne Atmospheric Observatory is a UK national facility run from within LGMAC for atmospheric chemistry research.
The work of LGMAC contributes to many international programmes including Intergovernmental Panel on Climate Change and the Global Ozone Assessment. LGMAC research is also very closely aligned with the IGBP SOLAS programme and the project offices are housed in LGMAC for the UK and international SOLAS programmes.
The members of LGMAC are mostly chemists and biologists but all recognise their work requires collaborations across many disciplines. Hence LGMAC operates as a loose cooperative internally and researchers maintain very strong links to other groups at UEA and world wide, particularly other marine and atmospheric scientists and the Earth System modelling group.
The Importance of Air-Sea Exchange
The School of Environmental Sciences has a tradition of interdisciplinary research at critical environmental boundaries, in this case the atmosphere/ocean boundary set in the context of the behaviour of the whole earth as a biogeochemical system. In terms of societal concerns LGMAC contributes significantly to our understanding of the mechanisms that will regulate future global change arising from anthropogenic emissions.
The Montreal and Kyoto protocols have marked a change in attitude within the international community to the issue of Global Change. Greenhouse gas emissions and ozone depletion are now recognised threats to the quality of life of the world's people and to the economies of the world that require strenuous efforts to counter. As a practical matter, nations must plan to meet the commitments made in these agreements, or face real economic penalties and international pressure. Transparent verification of greenhouse and ozone depleting gas sources and sinks is required.
At present, however, this political imperative is running well ahead of scientific knowledge. For example, from models which interpret our atmospheric and marine measurements of CO2, we know that the land and oceans are taking up a significant fraction of the CO2 emitted by man. But beyond that there is little scientific consensus as to where (which continent or ocean), or why (what processes are responsible) these sinks exist, or how long they will continue to act as they do today.
A second example is aerosols, which are now recognised as making a significant, but very poorly quantified, contribution to global climate change. They act to scatter light and create clouds thereby cooling the planet. Indeed the interaction of aerosols with climate is recognised as one of the major uncertainties in future climate predictions by the IPCC. However, their generation, chemistry and fate have received relatively little attention. Without a substantial maturing and deepening of our knowledge about these complex ocean/atmosphere interactions, scientists will be unable to provide the verification techniques and predictions of future trends which will make the Kyoto agreement work. Similar arguments apply to ozone depletion where, in spite of the success of the Montreal Protocol, ozone recovery is being delayed by the continued rise in brominated gases, CFC replacements and, potentially, global warming.
Simulations of future climate are only now beginning to incorporate the biological and chemical feedbacks which may arise as the atmosphere-ocean system changes in response to climate forcing. These simulations give divergent predictions depending on which feedbacks are included and how they are modelled. Substantial changes in "natural" sources and sinks of climatically active gases are possible, indeed probable, once significant climate change begins to take place. CO2 is the most studied example. However dimethylsulphide and other chemically active trace species such as organo-halogens which are released to the atmosphere as a result of algal growth in the oceans could also have important effects, little addressed to date. These deficiencies lead to uncertainties in the timing of global change effects by many decades, the social and economic implications of which are clearly profound. LGMAC aims to contribute significantly to reducing these uncertainties over the next decade.
The interactions between the ocean and the atmosphere are a "two way street". Not only do emissions from the oceans impact the atmosphere, but deposition of material from the atmosphere can affect the oceans. Human activity has doubled the rate at which nitrogen is "fixed" from the atmosphere and utilised by the biota. Emissions of nitrogen from combustion and agriculture fall into the ocean and can encourage algal growth. Dust mobilised from the great deserts is also carried through the atmosphere to the oceans where it releases iron which can also stimulate algal growth. Stimulation of algae by the deposition of iron and nitrogen will change the air-sea exchange of CO2, dimethylsulphide and other gases. This then provides a feedback to the atmosphere which may be important in regulating climate and LGMAC scientists are in the forefront of studying deposition to the oceans and its effects.
Links to Other Programmes
While dedicated to studying atmospheric and marine chemistry and composition, the new Laboratory will benefit from, and feeds into, other global change research particularly via the Climate Research Unit, Tyndall Centre, CSERGE and Zuckerman Institute for Connective Environmental Research, here at UEA, and research at other locations throughout the world. LGMAC scientists will also play a key role in international global change research projects particularly the IGBP SOLAS project.
Many aspects of the proposed scientific programme of LGMAC will address key unknowns in the post-Kyoto era, as well as helping to identify the new issues that may be of global concern in 10 or 20 years time.
Laboratory for Global Marine and Atmospheric Chemistry
School of Environmental Sciences
University of East Anglia
Norwich Research Park