The Concise Experimental Plan states that LBA is designed to create the new knowledge needed to understand the climatological, ecological, biogeochemical and hydrological functioning of Amazonia, the impact of land use change on these functions, and the interactions between Amazonia and the Earth system

The European Remote Sensing Group will both address important scientific questions which cannot be answered by in situ approaches alone, and also provide products of significance to other Thematic Groups not only from Europe but also from South America and the USA. Furthermore, some techniques will be transported to Brazil, and training provided for South American nationals. Both regionwide, and more local, remote sensing activities are planned, as outlined below.

I. Key LBA Research Issues to be Addressed

These will include:

• Monitoring, modelling and explanation of spatial and temporal variations of vertical water fluxes, and surface water balances over the whole of Amazonia during the entire LBA Project, with special reference to their chief positive and negative anomalies.
• Development of methods for the synergistic use of visible, infrared and passive microwave for further improved monitoring of rainfall.
• Investigation of possible approaches to Amazonia-wide evaluation and monitoring of soil moisture.
• Further development and validation of methods to delineate the spatial extent of inundated areas and of secondary forest stages using active microwave sensors.
• Development and implementation of an integrated system to monitor flooded and regrowth areas at regular short-term intervals.
• Further investigation and use of approaches to estimate biomass from active mircrowave data.
• Consideration of the potential impact of improved knowledge of tropospheric winds on the modelling of water fluxes over Amazonia and links with the General Circulation.
• Provision of improved datasets for other Themes, e.g. DEMs, and atmospheric trace constituents.

The key research activities to be undertaken by the European Remote Sensing Thematic Group include the following:

1. Identification and analysis of the magnitudes, scales, and natures of significant anomalies of key climatic/hydrologic variables within the Amazonian region. These variables will include:

• Rainfall
• Evapotranspiration
• Surface water balance

These will be monitored routinely using techniques being developed by CRS, University of Bristol, based primarily on geostationary visible and infrared data, and providing daily, 10-daily, and monthly products over the whole Amazonian region at a 25 x 25 km resolution, but also 5 x 5 km resolution products for special test sites, instrumented basins, field campaigns etc. as required by other Themes.

The Rainfall technique uses climate and weather station data for calibration, and will be a derivation of a method already applied over parts of eastern South America for 4 years. The Evapotranspiration and Surface Water Balance techniques will be similar to those already applied for over 4 years in West Africa, but not yet applied to South America, where initial spin-up will be undertaken prior to routine application, this after the end of Year 1.

Input datasets will be archived so that later method developments, based on comparisons with in situ and other satellite data, can be applied retrospectively to the whole LBA period.

The operational methodology will be transferred from CRS, University of Bristol to Brazil by the middle of the LBA Project, by which time the first Meteosat Second Generation (MSG) satellite will be in orbit. The improved infrared data from this satellite will provide the means for a further cycle of refinements of these techniques in the latter part of the LBA Project.

2. Development of methods for the incorporation of passive microwave data into the regional rainfall monitoring method, based on CRS experience as Precipitation Working Group leaders of NASA's WetNet Project, and research cloud development and rainfall processes using active microwave data from the new TRMM satellite.

3. In the later stages of LBA, development of a methodology for region-wide monitoring of soil moisture will be initiated, based on the surface water balance products generated under (1) above, along with surface morphology (via a DEM), soil maps, and vegetation inventories from other groups.

4. The need to delineate the spatial extent of inundated areas and of secondary forest stages at regular short term intervals (monthly to annual) has been identified and specified in the LBA Science Plan. Due to the frequent cloud cover and the equally frequent presence of smoke from forest fires microwave instruments are the most adequate tools for this purpose. Techniques to identify both inundated areas and secondary forest stages have been developed and investigated and will be further explored, in particular with respect to their applicability in an operational context.

5. Development and implementation of an integrated system to map flooded and regrowth areas at regular short-term intervals (monthly to annual): this work builds upon the experience of European groups during field campaigns in South America and Indonesia (where a similar activity is under way). A combination of satellite data and operational airborne radar is being pursued. Such a system would also be capable of monitoring forest fires.

6. Approaches to estimate biomass from multifrequency and multipolarization active mircrowave data will be further explored.

7. An improved satellite altimeter/SAR-based DEM of Amazonia will be prepared and provided.

8. The impact of improved tropospheric wind data on fluxes of moisture over Amazonia will be modeled in relation to Doppler wind observations from the proposed new Atmospheric Dynamics Mission of ESA, now advancing to Phase A, status in the context of the Earth Explorer Mission.

9. The GOME instrument on ERS-2 provides information on the vertical column ozone profiles. The new MIPAS instrument on ENVISAT will provide data relating to a wide range of atmospheric chemistry constituents. Attention may be paid to selected atmospheric constituents in conjunction with the Atmospheric Chemistry Thematic Group.

The work to be undertaken as the EU Remote Sensing contribution to LBA has been designed to complement that of the South American and USA contributions. Most specifically, the Amazonia-wide routine monitoring is designed to contextualize all local site and basin-scale investigations particularly in respect of the Physical Climate and Land Surface Hydrology Themes, and to provide up-scaling links to GCMs. Meanwhile, the anomaly products will help explain regional and secular variations in Carbon Storage and Exchange, Atmospheric Chemistry, and Land Use and Land Cover Change. In return, the US/Japanese TRMM Project will provide data (radar and other) from its Brazilian Field Campaign to help calibrate and validate the regular Amazonia-wide rainfall products, and data from existing and new local sites and test basins from other Themes will provide positive feedback into the evapotranspiration and surface water balance model development. The work using active microwave sensors is based on the experience of several European groups from satellite data analysis and aircraft campaigns in South America and Indonesia. It will be performed in close collaboration with non-European groups involved in related activities. It will be the emphasis of the European contribution to go one step beyond the methodological investigations towards an operational system. Airborne campaigns will also provide data of relevance to the macroscale remote sensing activities, helping to link point data with broad-area satellite data. Data from new ESA satellites (especially ENVISAT and MSG) will be used to further develop the satellite-based algorithms from the middle of LBA as they become operational, as will two of the new Candidate Earth Explorer Mission satellites, namely the Atmospheric Dynamics Mission and the Land-Surface Processes and Interactions Mission.

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