Environmental Chemistry from Space
Leo Salter
Cornwall College
ECG Bulletin
Cornwall College
ECG Bulletin
The RSC Environmental Chemistry Group was fortunate in attracting three exceptional speakers for this year’s Distinguished Guest Lecture and Symposium, which took place on March 3rd 2004 in the Meeting Room of the Linnean Society of London.
Dr Paul Monks (University of Leicester) opened the meeting with a presentation on “Probing the troposphere from space”. His description of the Earth System as a coupled multi-phasic land-sea-air system illuminated one of the salient reasons for satellite studies of the atmosphere – how can the Earth System be studied holistically unless from space? This is especially important in relation to long-range pollutant transport (twenty percent of any air pollution event is from a distant source) and for monitoring geopolitical initiatives such as Kyoto. However, Dr Monks also pointed out the difficulties associated with satellite measurements – the troposphere is a well-mixed layer some 10 km from the Earth’s surface and there are problems with studying this layer through the whole bulk of the atmosphere from a satellite 800/900 km up in a Low Earth Orbit. He explained that the satellite systems are an integral part of a network of measurement techniques for studying tropospheric chemistry. Land stations such as those at Mace Head in Ireland and Cape Grim in Tasmania provide single site data (spatially limited) and flights by research aircraft such as the BAE-146 provide snapshot data (temporally limited) to a data repository and then comparisons can be made to the continuous global coverage from satellites – “ . . . satellite measurements provide data which integrate the limited spatio-temporal scales of the each of the other techniques”.
In the second talk of the afternoon -“Remote-sensing of air-sea fluxes of CO2: constraining the global CO2 budgets” - Professor Jim Aiken from the Plymouth Marine Laboratory (PML) described work at the Centre for Observation of Air-Sea Interactions and Fluxes (CASIX) in supporting NERC initiatives on the quantification and understanding of the Earth System. Data from satellites are used to study phenomena such as the air-sea fluxes of chemical species, surface plankta distributions, marine biogeochemistry, sea temperature and ocean circulation processes – but with a focus on carbon dioxide fluxes, the core carbon cycle and global climate. Models are needed to exploit these data and to quantify carbon fluxes; three-dimensional models with coupled biology are being used (North Atlantic Model, North-West European Shelf Model). Satellites provide data on winds, sea surface temperature, solar radiation, and ocean colour to modellers, and these are used as an input to model parameterisation and also to measure the success of the models’ predictive capacities in relation to the carbon cycle. As always, the modellers seek more accurate data - which can only come from geostationary satellites.
Professor John Burrows (University of Bremen) closed the symposium with the ECG 2004 Distinguished Guest Lecture “Viewing the Earth’s environment from space: the challenges, the progress and the future.” He viewed the use of remote sensing via satellite as a means of obtaining objective data about the impacts of anthropogenic activities on the biogeophysical system, and delineated several crucial questions that needed a continuous programme of expansion in Earth Observation Systems. The enormous economic and social costs of climate change to the world community highlight the need for observations of emissions to the atmosphere – these are crucial for understanding the rate at which climate change is occurring and for detecting any successes in its amelioration. Ozone depletion was continuing to occur. The coupling of climate change with ozone depletion via phenomena such as the occurrence of polar mesospheric clouds meant that expectations of a post-Montreal Protocol smooth, continued, diminishment of the ozone hole might be confounded. Studies of NOx sources in the stratosphere, the impact of meteorites and solar proton events on the Earth’s atmosphere, the quantification of atmospheric aerosols, and surface temperature measurements are all dependent on satellite observations - because it is only via satellites (both Low Earth Orbit and Geostationary Earth Orbit) that data with adequate temporal and spatial resolution can be obtained.
Satellite measurements of the atmosphere began in the 1960s when the USSR attempted to measure ozone by UV spectrophotometry from space. Subsequently the NASA Nimbus series and other satellite systems improved and extended these early experiments. In 2002 the European Space Agency launched SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography).
This satellite (together with the GOME (Global Ozone Monitoring Experiment) series) has extensively increased the understanding of global pollution processes. Tropospheric nitrogen dioxide has been tracked from sources such as industrial centres in Japan and China, burning in Africa, South America and Indonesia, and the success of vehicular emission reduction technology in the US and Europe is clearly demonstrated by observations of continent-wide reductions in nitrogen dioxide concentrations. Cloud formation and growth has been examined via aerosol studies, chlorophyll-a is being tracked across the oceans, and reactive species such as OClO and BrO (which are crucial in ozone depletion) are being quantified.
Professor Burrows completed his lecture with a clear exposition of the arguments for extending the range and accuracy of satellite data via the use of advanced technology detectors in geostationary satellites. More accurate data would provide continuous regional-scale information for policy development and regulatory purposes, reduce the need for ground stations (and avoid their limitations) and assist co-operative actions by the global community for the benefit of us all.
Dr LEO SALTER,
Cornwall College,
Pool, Redruth, Cornwall
This summary first appeared in ESEF News, Issue No. 2, Spring 2004. More detailed accounts of these three presentations will appear in the January 2005 issue of the ECG Bulletin.
Dr Paul Monks (University of Leicester) opened the meeting with a presentation on “Probing the troposphere from space”. His description of the Earth System as a coupled multi-phasic land-sea-air system illuminated one of the salient reasons for satellite studies of the atmosphere – how can the Earth System be studied holistically unless from space? This is especially important in relation to long-range pollutant transport (twenty percent of any air pollution event is from a distant source) and for monitoring geopolitical initiatives such as Kyoto. However, Dr Monks also pointed out the difficulties associated with satellite measurements – the troposphere is a well-mixed layer some 10 km from the Earth’s surface and there are problems with studying this layer through the whole bulk of the atmosphere from a satellite 800/900 km up in a Low Earth Orbit. He explained that the satellite systems are an integral part of a network of measurement techniques for studying tropospheric chemistry. Land stations such as those at Mace Head in Ireland and Cape Grim in Tasmania provide single site data (spatially limited) and flights by research aircraft such as the BAE-146 provide snapshot data (temporally limited) to a data repository and then comparisons can be made to the continuous global coverage from satellites – “ . . . satellite measurements provide data which integrate the limited spatio-temporal scales of the each of the other techniques”.
In the second talk of the afternoon -“Remote-sensing of air-sea fluxes of CO2: constraining the global CO2 budgets” - Professor Jim Aiken from the Plymouth Marine Laboratory (PML) described work at the Centre for Observation of Air-Sea Interactions and Fluxes (CASIX) in supporting NERC initiatives on the quantification and understanding of the Earth System. Data from satellites are used to study phenomena such as the air-sea fluxes of chemical species, surface plankta distributions, marine biogeochemistry, sea temperature and ocean circulation processes – but with a focus on carbon dioxide fluxes, the core carbon cycle and global climate. Models are needed to exploit these data and to quantify carbon fluxes; three-dimensional models with coupled biology are being used (North Atlantic Model, North-West European Shelf Model). Satellites provide data on winds, sea surface temperature, solar radiation, and ocean colour to modellers, and these are used as an input to model parameterisation and also to measure the success of the models’ predictive capacities in relation to the carbon cycle. As always, the modellers seek more accurate data - which can only come from geostationary satellites.
Professor John Burrows (University of Bremen) closed the symposium with the ECG 2004 Distinguished Guest Lecture “Viewing the Earth’s environment from space: the challenges, the progress and the future.” He viewed the use of remote sensing via satellite as a means of obtaining objective data about the impacts of anthropogenic activities on the biogeophysical system, and delineated several crucial questions that needed a continuous programme of expansion in Earth Observation Systems. The enormous economic and social costs of climate change to the world community highlight the need for observations of emissions to the atmosphere – these are crucial for understanding the rate at which climate change is occurring and for detecting any successes in its amelioration. Ozone depletion was continuing to occur. The coupling of climate change with ozone depletion via phenomena such as the occurrence of polar mesospheric clouds meant that expectations of a post-Montreal Protocol smooth, continued, diminishment of the ozone hole might be confounded. Studies of NOx sources in the stratosphere, the impact of meteorites and solar proton events on the Earth’s atmosphere, the quantification of atmospheric aerosols, and surface temperature measurements are all dependent on satellite observations - because it is only via satellites (both Low Earth Orbit and Geostationary Earth Orbit) that data with adequate temporal and spatial resolution can be obtained.
Satellite measurements of the atmosphere began in the 1960s when the USSR attempted to measure ozone by UV spectrophotometry from space. Subsequently the NASA Nimbus series and other satellite systems improved and extended these early experiments. In 2002 the European Space Agency launched SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography).
This satellite (together with the GOME (Global Ozone Monitoring Experiment) series) has extensively increased the understanding of global pollution processes. Tropospheric nitrogen dioxide has been tracked from sources such as industrial centres in Japan and China, burning in Africa, South America and Indonesia, and the success of vehicular emission reduction technology in the US and Europe is clearly demonstrated by observations of continent-wide reductions in nitrogen dioxide concentrations. Cloud formation and growth has been examined via aerosol studies, chlorophyll-a is being tracked across the oceans, and reactive species such as OClO and BrO (which are crucial in ozone depletion) are being quantified.
Professor Burrows completed his lecture with a clear exposition of the arguments for extending the range and accuracy of satellite data via the use of advanced technology detectors in geostationary satellites. More accurate data would provide continuous regional-scale information for policy development and regulatory purposes, reduce the need for ground stations (and avoid their limitations) and assist co-operative actions by the global community for the benefit of us all.
Dr LEO SALTER,
Cornwall College,
Pool, Redruth, Cornwall
This summary first appeared in ESEF News, Issue No. 2, Spring 2004. More detailed accounts of these three presentations will appear in the January 2005 issue of the ECG Bulletin.