Organisation

Reconstruction of East Asian monsoon seasonality during the last glacial period

Dr. C.J. (Kay) Beets
VU University Amsterdam

13 January 2010

Because of the large impact of the summer monsoon rains on the East Asian environment, it is important to understand how natural changes in this climate system operate on longer and shorter time-scales. Land snails store the isotopic signature of precipitation (δ¹⁸O) and vegetation (δ¹³C) on which they live in the growth increments of their aragonitic shells. Therefore, the study of fossil mollusks from Chinese loess deposits can provide detailed information on seasonal changes in precipitation (and vegetation) over long time-scales (10³-10⁴ years). In this talk I will present the reconstructed seasonality over the last glacial cycle from the Mangshan loess section in central China, and discuss the impact of the large changes in seasonality during this period on the environment.

Late Quaternary eolian dust dispersal patterns across the Chinese Loess Plateau inferred from decomposed loess grain-size records

Dr. M.A. (Maarten) Prins
VU University Amsterdam

13 January 2010

The grain-size distributions of loess-paleosol sequences may provide valuable information on sediment provenance, transport pathways and paleoclimate variability. Here it is shown that a genetically meaningful decomposition of a series of Late Quaternary loess grain-size records extending across the Chinese Loess Plateau can be accomplished with the end-member modelling algorithm EMMA.

A genetic interpretation and the paleoclimatic significance of the mixing model(s) are provided by (i) comparison of the modelled end members with modern dust samples in terms of their GSD and flux rates, and (ii) a variety of geochemical analyses (REE and trace elements, ⁸⁷Rb/⁸⁶Sr - ⁸⁷Sr/⁸⁶Sr systematics, and U-Pb ages) of specific mineral fractions (K-feldspar, plagioclase, zircons) extracted from narrow size fractions belonging to specific modelled end-members. Such analyses provide transport-invariant measures of sediment composition in which effects of selective transport due to variations of grain size and density can be ignored, and therefore allow the provenance determination of the modelled end-members.

The unmixing results in conjunction with loess accumulation rate estimates reveal that two contrasting dust supply patterns were active over the Loess Plateau during the last glacial-interglacial cycle: (i) a background sedimentation pattern that was dominant during interglacial periods, especially over the central and southern parts of the Loess Plateau, is reflected by the constant flux of the fine-grained loess component, (ii) an episodic, highly variable dust input pattern, that was dominant during glacial periods throughout the Loess Plateau and noticeable during interglacial periods mainly over the northern Loess Plateau and almost disappearing over the southern Loess Plateau, is reflected in the admixture of two coarse-grained loess components.

Modeling of land-atmosphere interactions at regional scale

Ir. H.W. (Herbert) ter Maat
Alterra Wageningen

16 September 2009

In this presentation an overview will given of the possibilities of a regional atmospheric model (RAMS) to study feedbacks between the land surface and the atmosphere. The model is 3D, non-hydrostatic based on fundamental equations of fluid dynamics and includes a terrain following vertical coordinate system. One of the advantages of RAMS is the possibility to perform simulations on high resolution meshes to model small-scale atmospheric systems.

Two cases will be presented in which the importance of the land surface on atmospheric processes will be addressed. The cases will be:

1. the central part of The Netherlands (Veluwe), where the influence of topography and land use on the precipitation will be addressed, and
2. Southwest Saudi Arabia, where plans have been in exploratory stages of development to construct large scale irrigation works in its coastal plains

The basic mechanism is that a land cover or landuse change modifies the radiation balance and the subsequent partitioning of available energy over sensible or latent heat fluxes. These are first order effects and their relative importance may vary spatially and in time. Differences in latent and sensible heat input lead to altered heat and moisture content of the atmospheric boundary layer (ABL). ABL temperature and humidity feed back to the surface through stomatal behaviour of plants, creating a first potential loop. ABL temperature and humidity affect convective heating, total diabatic heating, subsidence, monsoon-flow strength and moisture convergence. These processes all affect cloud formation and as clouds strongly affect radiation a second potential feedback loop comes into play.

Soil evaporation - challenges

Dr.ir. Klaas Metselaar
Soil Physics, Ecohydrology and Groundwater Management
Wageningen University

1st of April 2009

There are several reasons why soil evaporation is of interest to hydrologists. One of them is the present idea that soil evaporation is non-productive loss of water in agriculture - this has led to the concept of vapour shift in discussiosn of water management options for the future. A similar concept is that of regarding soil evaporation as a loss to groundwater recharge. Both issues raise the question: what do we know at present about soil evaporation, and what is its magnitude - for cropped soils, for bare soils. The talk addresses this issue.

Ecohydrology in water-limited environments using quantitative remote sensing – the Heihe River basin (China) case

Dr. Xiaomei Jin, School of Water Resources and Environment, China University of Geosciences, Beijing, 100083, China

26th of February 2009

The study integrated remote sensing method with ecohydrology to quantifying the relationship between the water resources and the vegetation from large scale in the Heihe River basin, northwest China. The main contribution of this work is the development of the new methods for (i) quantitatively assessment of the spatial distribution of the vegetation and its impact factors in the mountainous area; (ii) accuracy estimation of the regional evapotraspiration and the validation of the evapotranspiration from water budget; (iii) quantifying understanding the important effects of surface water and groundwater on the vegetation growth. Furthermore, a new particularly useful framework for evaluating the eco-environmental changes from large scale in arid area was presented in this work.

Satellite retrievals of cloud PHYSICAL properties for CLimate studies

Dr. Rob Roebeling, KNMI Weather Services - Research and Development, De Bilt, The Netherlands

8th October 2008

Accurate information on cloud physical properties is required to increase our understanding of the role of clouds in the current climate system. An algorithm for retrieval of Cloud Physical Properties (CPP) from visible and near-infrared reflectances from meteorological satellite instruments (AVHRR & SEVIRI) is presented. This algorithm retrieves cloud optical thickness, effective radius, and liquid water path, whereas a cloud model is used to simulate cloud geometrical thickness and droplet number concentration. The comparability of the retrievals from the different instruments is hampered by large calibration uncertainties (up to 25%).

A recalibration procedure is developed that successfully reduces these uncertainties to less than 5%. To verify the validity of the SEVIRI cloud liquid water path retrievals one year of 15-minute SEVIRI data is compared against ground-based microwave radiometer observations. Due to the statistical significance of the dataset the resulting liquid water path retrieval accuracies provide a benchmark, and show very good agreement during summer while an overestimation is observed during winter. The sensitivity of cloud property retrievals is evaluated for errors in radiative transfer simulations and viewing geometries, and differences between assumed clouds (plane-parallel) and real clouds.

A five-year dataset of SEVIRI cloud properties is used to evaluate diurnal cycles of cloud properties in the Regional Atmospheric Climate Model (RACMO) for ocean, continental and Mediterranean climate regimes over the Eastern Atlantic and Europe. Moreover, we show that this dataset can be used for the prediction of rain rates and studies on interactions between aerosols and clouds. Although this presentation concentrates on the application of cloud physical properties retrievals for monitoring climate change and evaluating parameterizations of cloud processes in climate models, these retrievals can also be used for assimilation in weather prediction models or for studying the changes in the hydrological cycle.

Dr. Rob Roebeling holds a PhD in Environmental Sciences (2008) from Wageningen University, on Cloud Properties Retrievals from Satellite Observations. In 1991 and 1992 he worked at the dlo-Staring Centrum in Wageningen on surface flux retrievals from satellite data. In the period 1993-1999 he worked at the Environmenal Analysis and Remote Sensing Ltd. as a consultant in the field of boundary layer meteorology and crop growth modeling. He has been project leader of several national and international projects. Dr. Roebeling has been employed at KNMI since 2000, where he works as Senior Scientist on cloud properties retrievals from meteorological satellites. He is principle investigator for the cloud property retrievals within the Climate Monitoring Satellite Application Facility of EUMETSAT (CM-SAF). Furthermore, he is leading scientific projects in the fields of atmospheric radiative transfer and multi-sensor cloud remote sensing.

Water accounting: Virtual water transfers and water footprints

Prof. Arjen Hoekstra, University of Twente

10 September 2008

Since the Dublin conference in 1992 it is widely acknowledged that water is a scarce resource and should thus be considered as an economic good. Nevertheless, worldwide water is still not valued as such in decisions that affect water use, often resulting in over-exploitation and pollution. Decisions that affect water use are generally not even recognised as such. Consumers of water-intensive products generally have no clue of the fact that they make a demand on a scarce resource, because water is generally grossly underpriced, so that water scarcity is not properly reflected in the price of products. Any form of information about underlying water use has been lost once products arrive at the consumer. In addition to this, there is the ungrounded idea that water scarcity is to be understood and addressed as a phenomenon at local level or the level of a river basin at most. Research has shown, however, that about 15% of the water use in the world is for making products for export, which is expected to increa e in the future, giving a global dimension to water as an economic input factor. During the past six years a new analytical framework has been developed that helps to make explicit the so far hidden link between consumption and water use on the one hand and the invisible global dimension of water scarcity on the other hand. This new framework has become known under the heading of 'water footprint and virtual water trade accounting'. It has been made applicable for inclusion in the environmental accounts of both nations and businesses.

The water footprint is an indicator of water use that looks at both direct and indirect water use of a consumer or producer. The water footprint of an individual, community or business is defined as the total volume of freshwater that is used to produce the goods and services consumed by the individual or community or produced by the business. Water use is measured in terms of water volumes consumed (evaporated) and/or polluted per unit of time. A water footprint can be calculated for any well-defined group of consumers (e.g. an individual, family, village, city, province, state or nation) or producers (e.g. a public organization, private enterprise or economic sector). The water footprint is a geographically explicit indicator, not only showing volumes of water use and pollution, but also the locations.

The new water accounting framework can serve as a basis for developing innovative strategies to mitigate problems that relate to the increasing global freshwater scarcity. One of such strategies is to promote water neutrality among businesses, encouraging or compelling them to reduce and offset the negative social and environmental impacts of their water usage. Another instrument is to create a system of (tradable) water footprint permits, a Kyoto-protocol-like system defining a maximum global water footprint, which is allocated among participating countries, favouring the fair allocation of global water resources among the people of the Earth. Yet other instruments proposed are an international water pricing protocol, water labelling of water-intensive products and water certification of businesses.

Arjen Y. Hoekstra is Professor in Multidisciplinary Water Management at the University of Twente, the Netherlands. He specialises in integrated water resources planning and management, river basin management, policy analysis, and systems analysis. Hoekstra has an MSc degree in Civil Engineering and a PhD degree in the field of Water Systems and Policy Analysis, both from the Delft University of Technology. He has working experience in various academic environments in the Netherlands and abroad and has been project leader of a number of interdisciplinary research projects. Hoekstra is creator of the water footprint concept and established the interdisciplinary field of water footprint and virtual water trade analysis, a research field addressing the relations between water management, consumption and trade (www.waterfootprint.org). His publications cover a wide range of topics related to water management and include the books Perspectives on Water (1998) and Glob lization of Water (2008).

Dynamics of Land - Atmosphere Interaction: From Turbulence to Vegetation Competition Timescales

John D. Albertson, Professor
Department of Civil and Environmental Engineering, Duke University, Durham, NC USA

14 August 2008

The rates of mass and energy exchange between the land and the atmosphere are affected both by processes at the land surface (e.g. photosynthesis, radiative transfer, transpiration, etc.) and by the efficiency with which the turbulent boundary layer transports the mass and energy toward or away from the active surfaces. The structure and state of the vegetation at the land surface affect both the surface processes and the turbulence regime.
This talk addresses two key aspects of this system: 1) the connection between observable vegetation features (e.g. canopy height, leaf area index, etc) and the structure of the coherent eddies responsible for the turbulent transport, and 2) how hydrologically driven changes in vegetation density over time lead to changes in the exchange processes at the land surface. The ultimate goal is to support the modeling of vegetation changes over time and the resulting impacts to land surface exchange processes and vertical transport in the lower atmosphere. The connection etween vegetation structure and the turbulence regime is examined using proper orthogonal decomposition of large eddy simulations of atmospheric boundary layer turbulence. The feedbacks between hydrological processes and vegetation density are examined using field data and vegetation dynamics modeling for a southern African savanna site and a Mediterranean site on the island of Sardinia.

Improving Seasonal Hydrological Prediction at NCEP via Land Surface Modeling

Michael Ek, Land-Hydrology Team
US National Weather Service/National Centers for Environmental Prediction/Environmental Modeling Center (NWS/NCEP/EMC)

24 June 2008

We present progress by NCEP/EMC and collaborators in constructing and executing an uncoupled high-resolution monitoring and seasonal prediction system over the continental United States using five land-surface models, including the NCEP/EMC Noah land model. This uncoupled land-modeling approach includes both an analysis/monitoring mode and an ensemble seasonal prediction mode, with a focus on soil moisture, winter snowpack, and drought monitoring and prediction.

Land Use Changes and Conservation of Water Resources in Himalayan Headwaters

Prof. Prakash Tiwari
Associate Professor of Geography at Kumaon University,
Nainital, state of Uttarakhand, India

May 29, 2008

Himalaya forms the tallest water tower of the world where the mighty glaciers and mountain slopes constitute the source of the most of the rivers of South Asia. The regime of water resources in Himalaya is changing rapidly with respect to water discharge, volume and availability, primarily due to global as well as local environmental changes. During recent past, traditional resource development structure has changed mainly in response to population growth and resultant increased demand of natural resources in Himalaya. This has intensified resource use pressure and brought about rapid land use changes in the region. As a result, hydrological regime of Himalayan headwaters has disrupted and groundwater recharge has decreased. These hydrological imbalances are discernible in terms of long-term decreasing trend of stream flow and diminishing discharge and drying of natural springs. About 45% springs in Himalaya have dried and stream discharge has reduced by about 15%. As a result, a large number of settlement including fast growing urban areas are facing great scarcity of water for all purposes, and agricultural productivity has declined undermining food and livelihood securities both in upland and lowland areas. It is therefore imperative to evolve a community and user oriented integrated water management framework for the critical headwaters.

Prakash Tiwari is Associate Professor of Geography at Kumaon University, Nainital located in newly carved Himalayan state of Uttarakhand in India. He is a mountain environment and natural resource management specialist, and worked with a number of institutions in India and abroad including Simon Fraser University, Canada, McMaster University, Canada; University of Toronto, Canada, University of Leipzig, Germany; Martin Luther University, Germany; University of Salzburg, Austria; and Tohoku University, Japan under the fellowship of reputed international organizations. At present, Dr. Tiwari is at Institute of Geography, Martin Luther University, Halle-Wittenberg, Halle, Germany as Mercator Visiting Professor of German Research Foundation (DFG). He is currently developing Remote Sensing & GIS based ‘Natural Resources Database Management System (NRDMS) for the State of Uttarakhand in India. Dr. Tiwari is also coordinating international projects on (i) Land Use Changes, and (ii) Vulnerable Mountain E osystems and Vulnerable Communities of in High Mountain of Monsoon Asia of Mountain Group of Monsoon Asia Integrated Regional Study (MAIRS) – A joint venture of SysTem for Analysis Research and Training (START) and Earth System Science Partnership (ESSP), and also associated as Project Associate with ‘Urbanization and Global Environmental Changes’ (UGEC) of International Human Dimension Programme (IHDP). He is a member of Indian Expert Group on ‘Indigenous Knowledge System’ of International Union of Forestry Research Organizations (IUFRO). He is also a Coordinating Partner of the international collaborative projects on Master’s Program on Environment and Biodiversity Management with university of Bergen, Norway, Kunming Institute of Botany, China and Tribhuwan University, Nepal. He the editor of International Journal of Geography and Regional Planning, and Member of the Editorial Board and Mapping Consultant to the Journal of the World Association of Soil and Water Conserva ion (WASWC). Dr. Tiwari is also associated with SEDIBUD of the International Association of Geo-morphologists, and monitoring its first key test site in Indian Himalaya.

A dual-pass microwave land data assimilation system for estimating soil moisture: Development and validation

Prof. Dr. Kun Yang
Institute of Tibetan Plateau Research
Chinese Academy of Sciences

April 10, 2008

The estimation of continuous regional soil moisture and the surface energy budget is crucial for studies of agricultural, hydrological, and atmospheric processes. This study presented a land data assimilation system that assimilates AMSR/AMSR-E low-frequency (6.9 and 18.7 GHz) brightness temperature into a LSM to improve the modeling of soil moisture and the surface energy budget. The data-assimilation system involves an embedded dual-pass technique. In Pass 1, key model parameters are automatically calibrated using satellite data and forcing data; Pass 2 produces the near-surface soil moisture and surface energy budget by assimilating satellite data. As the system integrates well-established global products of soil, vegetation, precipitation, radiation, and other meteorological parameters, it is easily applied.

The system was evaluated using in situ data at two CEOP reference site. The results demonstrate that simulations of soil moisture and the surface energy budget were improved compared with the case with no assimilation. In particular, the soil moisture and energy partition simulated using the assimilation system is less contaminated by negative biases in input precipitation data than the case with no assimilation. This result is encouraging in terms of producing reliable surface-energy budgets in remote regions such as Tibet and northwest China where precipitation-monitoring networks are sparse and input precipitation data are prone to large errors.

Kun Yang has obtained his Master of Engineering (1997) from Tsinghua University and PhD (2000) from University of Tokyo. He has worked at University of Tokyo for seven years and last year he was promoted to be a full professor at Institute of Tibetan Plateau Research, Chinese Academy of Sciences. His research fields are land-atmospheric processes and their interactions as well as land microwave data assimilation. Currently, he is working on how to assimilate various in situ and satellite data into a single system to estimate atmospheric heating over the Tibetan Plateau.

Recent advances on the land surface process research in the northwestern China

Prof. Dr. Jun WEN
Cold and Arid Regions Environment and Engineering Research Institute (CAREERI),
Chinese Academy of Sciences (CAS),
http://www.casnw.net/english/index.html

April 2, 2008

This presentation will introduce the recent advances of the land surface process research conducted in the northwestern China, which are funded by Chinese Academy of Sciences and Nature Science Foundation of China (NSFC). The objectives of these researches are to understand the land surface process in the cold, arid and semi-arid regions, and hence improve the accuracy of numerical weather forecast model, agriculture service and water resource management in these regions.

The presentation include 4 parts:

1. A brief introduction about the Cold and Arid Environmental and Engineering Research Institute (CAREERI), and its research focuses.
2. An Overview of the Loess Plateau Land Surface Process Field Experiments (LOPEXs) and the soil moisture retrieval results from ENVISAT ASAR data over the Loess Plateau.
3. A CAS International Partnership Program: Estimates of the Evapotranspiration over the Hei River Basin by using satellite remote sensing data.
4. The key environmental Issues of the Yellow River water resource region under the global warming scenarios. Prospect some interesting research topics and projects in this region, and explore new research topics and potential cooperative opportunity.

Dr. Jun WEN is a research scientist of the land surface process and satellite remote sensing at the Cold and Arid Regions Environment and Engineering Research Institute (CAREERI), Chinese Academy of Sciences (CAS), and the Chair of Plateau Atmospheric Physics Division at the CAREERI/CAS. He is currently involved in several projects relevant to the land surface process assessed from the ground field experiments and satellite remote sensing.

"This can't be true!" An adventure in the analysis of the behavior of subsurface contaminant plumes

Prof. Dr. Ruud J. Schotting
Professor of Quantitative Water Management
Environmental Hydrogeology Group
Faculty of Geosciences
Utrecht University

Thursday 13 march 2008, 15:45

Professor Peter Grathwohl of Tubingen University in Germany conducted laboratory experiments to determine the relationship between the length of stationary contaminant plumes and the subsurface processes involved.

He found that this length is inversely proportional to the transversal dispersion length, i.e. the mixing perpendicular to the average groundwater flow direction. This was a surprising and unexpected result. We used mathematical analysis to confirm this experimental result and were able to provide a rather simple mathematical proof. The results of the experiments were counter intuitive, but the mathematics showed that they were right.

Participatory planning and vulnerability reduction using GIS and Remote Sensing tools in Mozambique and in the Limpopo river basin

Mr. Mathias Spaliviero
Chief Technical Adviser - Mozambique
United Nations Human Settlements Programme (UN-HABITAT)

22 November 2007

The objective of the presentation is to show some of the activities developed by UN-HABITAT in recent years in Mozambique and in the Limpopo river basin, especially concerning participatory planning and reduction of the vulnerability. Emphasis will be given to the use of GIS and remote sensing tools.

The presentation is structured in 3 parts:

• Part 1: provides some background on Mozambique in terms of generic data, its high susceptibility to natural disasters, and gives a brief overview of the UN-HABITAT programme in that country.
• Part 2 explains the participatory planning approach as central method used by UN-HABITAT in all its activities in Mozambique and in the sub-region. GIS and remote sensing tools are of great importance in the implementation of such approach.
• Part 3 describes the objectives and results obtained of a recently concluded project funded by the Global Environmental Facility and executed by UN-HABITAT entitled "Sustainable land use planning for integrated land and water management for disaster preparedness and vulnerability reduction in the Limpopo river basin".

Irrigation water management in Murray Darling basin, Australia: Challenges and future prospects

Dr. Mohsin Hafeez
Research Scientist (Spatial Surface Water Hydrologist)
Common Wealth Scientific and Industrial Research Organization (CSIRO)
CSIRO Land and Water Division, Wagga Wagga, New South Wales, Australia
International Centre of Water for Food Security (IC Water), Charles Sturt University, Wagga Wagga, Australia

23 August 2007

Murray Darling Basin (MDB) is the most important basin for agricultural production in Australia; it consumes more than 70% of total water use in Australia. First, a brief overview will be given of the broader issues of water management in the MDB and then irrigation water management issues in the Murrumbidgee catchment (84,000 km2) are discussed. This catchment is located in central NSW; it ranges from semi-arid to alpine zones, and covers a range of soil and vegetation types that are typical for much of Australia. The Lower Murrumbidgee is currently classified as a global reference basin by the UNESCO HELP (Hydrology for Environment, Life and Policy) programme.
The research provides a complete analysis of water flows throughout the Murrumbidgee and Coleambally irrigation catchments, the development of innovative technology to rapidly detect channel seepage "hotspots", and the development of a decision support system linking geographic and economic information with water flows. This is a first assessm nt for any irrigated catchment in Australia which provides an opportunity to identify possible water savings and ways to increase the efficiency of water management for irrigated agriculture. The presentation will end with an overview of different ongoing research activities carried out by the researchers from the International Centre of Water for Food Security (IC Water) for water savings and demand management in the Murrumbidgee catchment in near real time.

• Research Scientist (Spatial Surface Water Hydrologist), CSIRO Land and Water Australia (Oct 2006 - current)
• Senior Lecturer (Adj), Charles Sturt University, Australia (Sep 2005 - current)
• Postdoctoral Fellow (Spatial Hydrologist), CSIRO Land and Water, Australia (Mar 2004- 2006)
• Postdoctoral Fellow (Hydrologist), University of Bonn, Germany (Dec 2002- Feb 2004)
• Junior Researcher (Hydrologist), University of Bonn, Germany (Sep 1999 – Nov 2002)
• Research scholar, International Rice Research Institute (IRRI), the Philippines (Jun 2000- May 2002)
• Visiting Scientist (Spatial Hydrologist), International Water Management Institute (IWMI), Sri Lanka, (Jul 2001- Sep 2001)
• Junior Hydro-geologist, International Water Management Institute (IWMI), Pakistan (Jan 1999 – Jul 1999)
• Associate Field Research Engineer, International Water Management Institute (IWMI), Pakistan (Mar 1998 – Dec 1998)
• Research Hydraulic Engineer, Centre of Excellence in Water Resources Engineering (CEWRE), University of Engineering and Technology, Pakistan (Dec 1996 – Feb 1998)
• Project Engineer (Design), Kaneko Agricultural Machinery Company (Pvt.) Ltd., Pakistan (Jun 1995 – Nov 1996)

Measuring soil surface water content using full-wave inversion of off-ground GPR data

Prof. Dr. Sébastien Lambot
Department of Environmental Sciences and Land Use Planning
Université catholique de Louvain, Belgium
ICG-4: Agrosphäre
Forschungszentrum Jülich, Germany

6 June 2007

Presentation (PDF, 5 MB)

Knowledge of the spatial distribution and dynamics of the surface water content at various scales is essential in agricultural, hydrological, meteorological, and climatological research and applications. Surface water content constitutes the boundary condition between the soil and the atmosphere and governs all important key processes such as infiltration, runoff, evaporation, as well as partitioning of energy at the earth's surface into sensible and latent exchange with the atmosphere. Existing techniques to characterize soil surface water content are either suited to small areal scales (<0.1 m), such as the gravimetric method, capacitive sensors, and time domain reflectometry, or to large areal scales (>10-100 m), such as airborne and spaceborne passive microwave radiometry and active radar systems. As yet, no practical method is available to measure the variability of soil surface water content at field or watershed scales, which is crucial in applications that include agricultural water managemen and soil and water conservation and to bridge the scale gap between airborne and spaceborne remote sensing and ground-truth measurements.

In that context, we propose a new ground-penetrating radar (GPR) method specifically designed for mapping in real time surface water content at the field scale. The radar system consists of a vector network analyzer combined with an off-ground ultrawide band monostatic horn antenna. Radar signal analysis is based on full-wave electromagnetic modeling and inversion, accounting in particular for all antenna effects, antenna-soil interactions, and wave propagation in three-dimensional multilayered media. Wave inversion is focused on the surface reflection in the time domain. The method presents considerable advantages compared to the current surface characterization methods using GPR, namely the ground wave and common reflection methods: (1) there is no time zero determination issues, (2) additional measurements for detecting the ground wave (which is moreover not always identifiable) are not required, (3) additional measurements above a perfect electric conductor situated at the same distance as the soil are not required as for the common reflection method, (4) the antenna height should not be known, and (5) the method is theoretically more accurate and robust as it is based on exact electromagnetic modeling. In particular, it is possible to take into account the effects of electric conductivity on the surface reflection when non-negligible and to include near-surface layering effects, which would lead otherwise to unrealistic values due to constructive or destructive interferences. We present a theoretical analysis of these two factors and they effects on the water content estimates. Finally, we present laboratory and field results (in the frame of the Aquiferex project in Tunisia) where the GPR measurements are compared to ground-truth gravimetric and time domain reflectometry data. The proposed method appears to be very appropriate in any applications where surface water content must be known at the field scale.

The ESA SAR missions and their exploitation for science and applications development

Yves-Louis DESNOS
Head Research and Development Section & Senior Advisor,
Science and Applications Department,
European Space Agency, ESRIN - ITALY

10 May 2007

Tropical forests and streamflow: What benefits are to be expected from forestation?

Dr. L.A. (Sampurno) Bruijnzeel
Faculty of Earth and Life Sciences, Vrije Universiteit, Amsterdam, The Netherlands

8 March 2007

There has been a growing disparity in recent years between ´public´ and ´scientific´ perceptions of the hydrological role of forests, and of forest plantations in particular. Traditionally, forests were considered useful in increasing rainfall and streamflow, and in reducing or even preventing floods, landslides and erosion. The perceived hydrological benefits of forests – mostly ascribed to the ´sponge effect´ - came under serious scrutiny in the early 1980s when L.S. Hamilton among others argued that forest removal generally increased rather than reduced water yields for both annual totals and dry season flows. Extreme flooding was attributed to high rainfall over large spatial and temporal extents and it was argued, that forest cover exerted little influence on watershed response since the entire soil system would become saturated. Hamilton et al. also recognized that post-forest soil degradation could reach an extent where the soil infiltration capacity is reduced beyond a critical level, causing massive increases in over-land flow for degraded hillsides and so impair soil- and groundwater reserve recharging. Not only would storm-flows, surface erosion and stream sediment loads increase during the rainy season, but base-flows would also be reduced during the dry season. Through emphasis (in various recent reports by influential bodies such as FAO and CIFOR) on the negative effects of forests on annual and seasonal water yields, the positive effects of forest cover receive less attention, thereby creating a sense of confusion in the (tropical) forestry decision-making world. This presentation seeks to give a more balanced account of the impacts of afforestation (tree planting) in the humid (sub-)tropics with respect to: (i) total catchment water yields, (ii) infiltration and storm-flow production, and (iii) dry season flows.

In the majority of cases studied, afforestation failed to produce the expected improvements of increased total and dry season water yields. However, for severely degraded lands, there was indirect evidence that afforestation could lead to increased dry season flows. Reductions in surface runoff after afforestation or restoration of degraded (sub-) tropical soils can be large enough to compensate the higher water uptake by trees, provided that rainfall exceeds potential evaporation. Comparable evidence from sub-humid areas is mostly anecdotal. Although afforestation is unlikely to positively affect total water yields, in coastal and montane areas with high fog incidence, tree planting could generate significant extra inputs through canopy fog interception and reduced vegetation use. Theoretically, benefits could also come from other land use systems, like agro-forestry and conservation cropping that are capable of maintaining a high degree of soil surface protection and infiltration capacity. In practice, t e situation is often very different given that the margins for the management of forests are much broader than those for cropping systems. Even sub-optimal forest management does not immediately degrade the hydrological functioning of an area. However, a high level of management or maintenance of soil conservation is required for agro-forestry and cropping to be equally effective in hydrological terms.

Finally, in areas where afforestation leads to lowered dry season water yields, this disadvantage should be weighed against the various benefits (carbon sequestration, biodiversity, protection against erosion, improved water quality) offered by a well-developed forest cover. Payment for Environmental Services (PES) schemes, in which lowland dwellers pay upland land-owners for sound management practices that safeguard water supply and quality, offer a promising framework for a balanced solution. Widespread implementation of PES schemes is currently hampered by an incomplete understanding of the effects of afforestation on dry season flows. Catchment experiments, supported by process studies and modelling, are urgently needed to resolve this matter.

Dr. Sampurno Bruijnzeel´s tropical research interests range from nutrient cycling in natural and planted forests, through erosion and sedimentation dynamics in deforested landscapes, to cloud forest hydrology, and effects of deforestation or reforestation on streamflow. Dr. Bruijnzeel´s research and literature reviews on the latter two subjects in particular have earned him the reputation of being a world’s leading expert on tropical forest hydrology and effects of forest conversion according to the nomination. Recently, i.e. on 6 June 2005, during the Annual Meeting of the Royal Geographical Society in London, Dr. Sampurno Bruijnzeel was awarded the prestigious Busk Medal 2005 for his contributions to ´biosphere research in the humid tropics´.

ESA's EO Programme and Future Missions dedicated to the Observation of Land Surfaces

Dr. Michael Berger
Land Surfaces Unit of the Mission Science Division (EOP-SML), Noordwijk, the Netherlands

11 January 2007

ESA's Earth Observation Programme is dedicated to serve the European remote sensing community's data needs, their continuity as well as the support for science and service extention. The programmatic framework is outlined in ESA's Living Planet Programme which recently has been updated into The Changing Earth outlining the New Scientific Challenges of the programme. Different progammatic components support ESA's overall EO objectives, as e.g. Earthnet allows access to data from non-ESA missions; the Earth Explorers, further subdivided into Opportunity and Core Missions, support the scientific aspects, and the GMES space component, supports the operational services with a long-term perspective. The different components of ESA's Earth Observation Programme and future missions dedicated to the observation of land surfaces will be introduced in the presentation.

Michael Berger received a master degree in geophysics (1989) and a PhD in remote sensing (1996) from the Ludwig-Maximilians University, Munich. He was employed as a scientist at the German Aerospace Research Establishment (DLR), the Geo-Research Center Potsdam (GFZ) and was working at the National Remote Sensing Facility in Harare, Zimbabwe as a long term expert for the German Technical Cooperation (GTZ). Since 1998 he is working at ESA-ESTEC in the Land Unit of the Mission Science Division and is responsible for the scientific definition and preparation of future ESA Earth Observations missions dedicated to the observation of land surfaces (SMOS, FLEX, Sentinel-2).

The GLOWA Volta Project: Towards a satellite-based observatory?

Prof. Dr. Ir. Nick van de Giesen
Water Management, Civil Engineering & Geosciences, Technical University Delft, Netherlands

2 November 2006

Prof. Dr. Ir. Nick van de Giesen
Water Management
Civil Engineering & Geosciences
TU Delft

The GLOWA Volta Project is a large interdisciplinary, long-term research project in the Volta Basin, West Africa. The project is funded by the German government and is presently entering its third phase, covering years seven through nine. Within the project, the natural scientists have come to the conclusion that remote sensing should be the basis for long-term monitoring and observation. The main reason for this conclusion is that ground observations are difficult to make and organize. Still, it would be necessary to make some strategic observations on the ground, which may be different from standard hydro-meteorological observations.

After a short introduction of the project, the presentation will cover some of the remote sensing applications that are thought to be of special interest. Some of these are non-standard applications such as the use of scatterometers for soil moisture estimates. The presentation will end with a reflection on the first hydrological satellite, SMOS, that will be launched next year. The hope is that ITC will work with VU Amsterdam and TU Delft in the calibration phase of SMOS.

• Delft University of Technology, 7/2004 until present
• Center for Development Research (ZEF) – Bonn University, 8/98 until 7/2004
• Cornell University, 1/98 until 8/98
• West Africa Rice Development Association, 12/94 until 12/97
• Cornell University, 10/93 to 10/94
• C.I.I.F.A.D., 6/91 to 9/92
• Cornell University, Assistantships, 8/89 to 5/91 and 10/92 to 9/93
• Netherlands Foundation for Scientific Research, 7/88 to 11/88
• Agricultural University of Wageningen, 4/88, 11/87, and 10/86 to 3/87
• National Irrigation Administration Philippines, 11/84 to 5/85

Polarimetric and Interferometric SAR for Geophysical Land Parameter Estimation

Dr. Irena Hajnsek
German Aerospace Center e.V. (DLR), Germany

12 October 2006

Dr. Irena Hajnsek
Research Group Leader
Research Group: Polarimetric SAR Interferometry (Pol-InSAR)
Department: SAR-Technology
Microwaves and Radar Institute
German Aerospace Center e.V. (DLR)
PO Box 1116, Wessling, Germany

Polarimeric SAR interferometry (Pol-InSAR) is today an established remote sensing technique that allows the investigation of the 3-D structure of natural volume scatterers. Interferometric observables are highly sensitive to the spatial variability of vertical structural parameters and allow accurate 3-D localisation of the scattering center. On the other hand, scattering SAR polarimetry is sensitive to the shape, orientation and dielectric properties of scatterers and allows the identification and/or separation of scattering mechanisms of natural media. In polarimetric interferometry both techniques are coherently combined to provide sensitivity to the vertical distribution of scattering mechanisms. Hence, it becomes possible to investigate the 3-D structure of volume scatterers and to extract information about the underlying scattering processes using only a single frequency polarimetric radar sensor. This promises a breakthrough in solving essential radar remote sensing problems. Indeed, structural para eters of volume scatterers in the biosphere and cryophere such as vegetation height, structure, biomass and soil moisture, or snow and ice depth, and layering are today critical inputs for ecological process modelling and enable monitoring and understanding of ecosystem change.

In this talk the principle of Pol-InSAR and an overview of the activities, advances and achievements using Pol-InSAR techniques and applications developed over the last five years will presented.

Irena Hajnsek received her Dipl. degree (Honors) in 1996 from the Free University of Berlin, Germany and the Dr. degree (Honors) in 2001 from the Friedrich Schiller University of Jena, Germany. From 1996 to 1999 she was with the Microwaves and Radar Institute (DLR-HF) of the German Aerospace Center (DLR), in Oberpfaffenhofen, Germany. From 1999 to 2000 she has been 10 months with Institut d’Electronique et de Télécommunications de Rennes at the University of Rennes, France I and 4 months with Applied Electromagnetics (AEL), a small research company in St. Andrews, Scotland, in the frame of the EC-TMR Radar Polarimetry Network. Since September 2000 she is at the Microwaves and Radar Institute (DLR-HF) of the German Aerospace Center (DLR), working on polarimetric and interferometric processing techniques, modelling of natural scattering processes, and, the development of inversion algorithms for physical parameters from SAR data. Since 2002 she is leading the Polarimetric SAR Imterferometry working gro p. Her main research interests are in electromagnetic propagation and scattering theory, radar polarimetry, SAR and Interferometric SAR data processing techniques.

The GO-FEWS project: Real-time assimilation of remotely-sensed soil moisture data into the Representative Elementary Watershed (REW) model for enhanced flood forecasting

Dr. Paolo Reggiani
WL Delft Hydraulics, Delft, Netherlands

20th April 2006

The GO-FEWS project involves the assimilation of real-time soil moisture data into a spatially-distributed process-based hydrological model with the purpose of investigating if operational flood forecasting in the Rhine-basin can be improved. The Representative Elementary Watershed (Reggiani & Rientjes, 2005) hydrological model has been chosen for the proposed investigation. Real-time soil moisture products are obtained from the AQUA AMSR-E sensor with a 50 km footprint by applying a soil moisture interpretation algorithm developed at the VUA (De Jeu & Owe, 2003).

The remotely sensed soil moisture data are assimilated into the hydrological model within the flood forecasting environment Delft FEWS, using the specialized data assimilation toolbox DA-TOOLS developed at Delft Hydraulics. The pilot application focuses on the Mosel river basin, a subsystem of the river Rhine.

The hydrological model is calibrated over a 10-year period on stream data for the basin. The performance of the approach is verified, using historical weather forecasts for the year 2003 in combination with soil moisture data for the same period. Simulations are first carried out without any data assimilation. Subsequently simulations with assimilated soil moisture for the upper soil layer are performed. The presentation will show the set-up of the project and some preliminary results.

• Masters in Environmental Engineering (University of Trento, Italy, 1994);
• PhD in Environmental Engineering 1999 (University of Western Australia Perth, Australia).
• Researcher at CSIRO (Commonwealth and Industrial Research Organisation) 1999.
• Marie Curie Fellow at LTHE (Grenoble) 2001.
• Since 2002 scientific researcher at WL Delft Hydraulics, The Netherlands.
• Principal activities: coordination of R&D projects, consulting activities in the water resources sector, research on flood forecasting and hydrology.

Progress in on-line data-assimilation and probabilistic forecasting of distributed hydrological systems

Prof. Marc F.P. Bierkens
Professor of Hydrology Utrecht University, Utrecht, Netherlands

16th March 2006

Marc F.P. Bierkens and Hanneke M. Schuurmans
Department of Physical Geography
Utrecht University

We present a general framework for on-line data assimilation and probabilistic forecasting of distributed hydrological systems. The different components of this framework are presented and case studies are used to show preliminary results of these components. In particular we look at on-line precipitation prediction using rain gauges and radar data, assimilation of in-situ observations using. The ensemble-Kalman filter and probabilistic forecasting using the ECWMF ensemble forecasting system. We also present future ways to incorporate remote-sensing information (Visible/Infrared fir evaporation and passive microwave for soil moisture).

Finally, we present the experimental setup of the Langbroekerwetering test area where invaluable combinations of remote sensing and in situ hydrological data are collected.

Prof. Dr. Marc F.P. Bierkens holds the chair in Geographical Hydrology at the Department of Physical Geography at Utrecht University. Marc Bierkens (1965) received his MSc in Hydrology from Wageningen University (1990), a PhD in Physical Geography from Utrecht University (1994) and became professor of Hydrology at Utrecht University in 2002. He is also partly employed by TNO Institute of Applied Geosciences. In between 1994 and 2002 he worked as a senior scientist and team leader at Alterra Research institute in Wageningen. Marc Bierkens' fields of expertise are groundwater hydrology, stochastic hydrology, hydrological regionalisation, upscaling theory and geostatistics. Recently initiated work comprises integrated modelling of soil-water-vegetation dynamics, data-assimilation methods for operational water management and global scale hydrological modelling in relation to climate.

Marc Bierkens is a member of the European Geosciences Union, the American Geophysical Union and the International Association of Hydrological Sciences. He co-organised the IAHS ModelCARE conference in 2005 in The Netherlands. Marc Bierkens (co-) authored 85 publications, 30 of which appeared in international peer-reviewed journals. He is principal author of the book "Upscaling and Downscaling Methods for Environmental Research" (2002) and co-author of the book "Sampling for Natural Resource Monitoring" (2006).

Current challenges in catchment hydrology - Experiments and modelling

Prof. Stefan Uhlenbrook, PhD, MSc,
Professor of Hydrology, UNESCO-IHE Institute of Water Education.

16th February 2006

A major challenge in catchment hydrology is to improve our understanding of hydrological processes at different scales and to define appropriate model structures for process-based predictions at catchment scale. This talk will review recent progresses in exploring runoff generation processes using hydrochemistry, environmental tracers and geophysical methods (i.e. electrical resistivity tomography, ERT) at the hill slope and small catchment scale. In addition, the incorporation of process understanding into catchment models for larger scale predictions is discussed. Particular attention will be paid to the benefit of process data to reduce the prediction uncertainty of catchment models.

Professional Experiences

Honors

Research and monitoring at the atmospheric observational facility Cabauw

Dr. Fred C. Bosveld, KNMI

24th January 2006

Through the cooperation of 6 national institutes in the consortium CESAR, Cabauw has become one of the most important single site atmospheric facilities in the world. The CESAR consortium consists of KNMI, TUD, RIVM, WUR, ECN and TNO-FEL. Recently this cooperation is strengthened by the approval of a large project within the national program BSIK-climate for space. The goal is to acquire a coherent set of observations of the atmospheric column over Cabauw for:

1. development and evaluation of atmosphericmodels,
2. the development and validation of satellite product and
3. monitoring of trends.

In this presentation the CESAR consortium will be introduced and an overview of its international position will be given. Instrumentation and data products will be discussed and some examples of research with the Cabauw observations will be shown.

Fred Bosveld is at the Royal Netherlands Meteorological Institute (KNMI) since 1985. In the period 1988-1996 he worked on field programmes at the KNMI forest site Garderen. He got his PhD in 1999 from the Agricultural University Wageningen on a thesis titled: "Exchange Processes between a Coniferous Forest and the Atmosphere". In 1994 he became involved in the experimental programmes at the Cabauw meteorological mast. He worked on the preparation of Cabauw data sets for use in the Project for Intercomparison of Land surface Parameterisation Schemes, Phase 2. Since 2000 he is involved in the preparation and organisation of the observational infrastructure at and around the 213 m meteorological tower in Cabauw. He is responsible for the tower and land surface exchange observations at the site. Research is focussing on stable boundary layers, and the local budgets of momentum heat, water and CO2.

Study on Land Surface Heat Fluxes and Water Cycle over the Tibetan Plateau

Prof. Dr. Yaoming Ma, Chinese Academy of Sciences (CAS),
More information about the Institute of Tibetan Plateau Research (ITP), the Chinese Academy of Sciences (CAS) can be seen at http://www.itpcas.ac.cn/system/english.asp.

27th October 2005

As the most prominent and complicated terrain on the global, the Tibetan Plateau, with an elevation of more than 4000 m on average above mean sea leave makes up approximately one fourth of the land area of China. Long-term operation and research on the Tibetan Plateau have shown that the giant prominence expert thermal effects on the atmosphere, thus greatly influencing circulations over China, Asia and even the global. Due to its topographic character, the plateau surface absorbs a large amount of solar radiation energy and undergoes dramatic seasonal changes of surface heat and water fluxes. The lack of quantitative understanding of interactions between the land surface and atmosphere makes it difficult to understand the complete energy and water cycles over the Tibetan Plateau and their effects on the Asian Monsoon system by numerical models. Therefore, the study on energy exchange and water cycle are regarded as the main task in the GEWEX (Global Energy and Water cycle Experiment) Asian Monsoon Experim nt on the Tibetan Plateau (GAME/Tibet, 1996-2000) and CEOP (Coordinated Enhanced Observing Period) Asia-Australia Monsoon Project (CAMP) on the Tibetan Plateau (CAMP/Tibet, 2001-2005). The intensive observation and long-term observation of the GAME/Tibet and the CAMP/Tibet have been done successfully in the past 8 years. A large amount of data has been collected, which is the best data set so far for the study of land surface heat flux and water cycle over the Tibetan Plateau. Firstly, the field experiments and some results on the local land surface fluxes partitioning ("imbalance", diurnal variation, inter-monthly variation, inter-yearly variation and vertical variation etc) will be presented.

The study on the regional distribution of land surface heat fluxes is of paramount importance over heterogeneous landscape of the Tibetan Plateau and it is also one of the main scientific objectives of GAME/Tibet and CAMP/Tibet. Therefore, the derived regional distribution and seasonal variation of surface variables (surface reflectance and surface temperature); vegetation variables (NDVI, MSAVI, vegetation coverage and LAI) and surface heat fluxes (net radiation flux, soil heat flux, sensible and latent heat flux) are also presented by combining 3 NOAA/AVHRR images with field observations.

In order to upscale the land surface heat fluxes to the whole Tibetan Plateau area, the Institute of Tibetan Plateau Research (ITP) of the Chinese Academy of Sciences (CAS) is establishing a Monitoring and Research Platform (MORP) for land surface and atmospheric processes on the Tibetan Plateau. The establishing and monitoring plan of long-term scale (10 years) and short-term scale (3-5 years) of the MORP will also be introduced here.

Prof. Yaoming Ma is leading scientist of the study on land surface and atmospheric processes at the Institute of Tibetan Plateau Research (ITP), Chinese Academy of Sciences (CAS), Chinese overall coordinator of GEWEX Asia Monsoon Experiment on the Tibetan Plateau (GAME/Tibet) and Coordinated Enhanced Observing Period (CEOP) Asian-Australian Monsoon Project (CAMP) on the Tibetan Plateau (CAMP/Tibet), and the director of Comprehensive Observation and Research Station on Mt.Qomolangma (Mt.Everest), Chinese Academy of Sciences.

Measurement of the space-time variability of rainfall using ground-based remote sensing techniques

Dr. Ir. Remko Uijlenhoet, Hydrometeorology Project Leader, Hydrology and Quantitative Water Management Group Department of Environmental Sciences Wageningen University".

4th October 2005

Hydrometeorology is concerned with the exchange processes between the terrestrial and the atmospheric component of the hydrological cycle: Precipitation and evaporation. These fluxes exert a major influence on the water and energy budget of the land surface and the lower atmosphere. Rainfall and (potential) evaporation are still traditionally measured at the point or local scale, inconsistent with the grid size of most hydrological and meteorological models and with the resolution of most remote sensing techniques. We present an overview of hydro meteorological research in the Hydrology and Quantitative Water Management Group at Wageningen University, with a special focus on the measurement and parameterization of the space-time variability of rainfall using ground-based remote sensing techniques.

Remko Uijlenhoet graduated in 1990 from Wageningen University with an MSc degree in Hydrology and Water Resources. In 1999 he obtained his PhD degree from the same university for a PhD thesis entitled "Parameterization of Rainfall Microstructure for Radar Meteorology and Hydrology". From 1997 to 1999 he was a Marie Curie Fellow at the Laboratoire d´Etude des Transferts en Hydrologie et Environnement (LTHE) in Grenoble, France. From 2000 to 2001 he was a research associate in the Water Resources Program at Princeton University, USA. In 2001 he received a 5-year NWO Vernieuwingsimpuls grant, which has allowed him to set up his own research team in Hydrometeorology, within the Hydrology and Quantitative Water Management Group at Wageningen University. In addition to the project leader, the hydrometeorology team currently consists of 1 postdoc and 4 PhD students. The main research topic is the measurement and parameterization of the space-time variability of rainfall using ground-based remote sensing techniques.

ELDAS

Bart van den Hurk, KNMI

14th June 2005

ELDAS (European Land Data Assimilation System) is a recently completed European project where European expertise on the estimation of soil moisture content on a contental scale was combined. In the presentation an overview is given on soil moisture data assimilation as routinely applied in Numerical Weather Prediction applications, and some results of ELDAS are present. A number of forcing and validation data bases were constructed, a common data assimilation framework was applied, and test experiments were conducted. These show that the data assimilation improved the partitioning of available energy over evaporation and sensible heat. Also, the high quality forcing database may prove to be useful for crop prediction applications. On the other hand, the data assimilation did not improve the skill of a number of hydrological flood forecasting applications. Also, the present configuration results in fairly large artificial soil moisture corrections over Europe, that are likely not related to atmospheric dryi g conditions.

Bart van den Hurk is senior researcher at KNMI. He coordinated the ELDAS project, but since recent year his work is more devoted to aspects of regional climate modelling, with a special focus on the European hydrological cycle. From 1 March 2005 he is part-time professor at Utrecht University, at the IMAU department.

Research activities of the Department for Water Engineering and Management, University of Twente

Prof. Dr. Suzanne Hulscher, Twente University

Thursday 21st April 2005

The department for Water Engineering and Management deals with the management of large, mainly natural, surface water bodies, such as rivers, estuaries and seas. In our research two distinct lines of investigation can be distinguished: one the physics of water systems, the second analysis of the management of such systems. This presentation is will provide an overview of these research activities, with examples both for rivers and for seas.

In more detail, the research line of "Physics of water systems" will be discussed. This is required to improve the management of large-scale surface water systems such as rivers and shallow seas. WEM aims to improve understanding of the physical processes and to model their behaviour appropriately, which means as simple as possible but accurate enough for the water management problems that are considered.

Suzanne Hulscher was born in 1966 and graduated in 1991 at Utrecht University, Faculty of Physics and Astronomy (M.Sc. Theoretical Physics, with Mathematics as a minor). She obtained her PhD in 1996 on Physical oceanography, also at Utrecht University. Before she started her career at the University of Twente she has worked at IMAU and WL|Delft Hydraulics. From 1996 she was appointed at the University of Twente. First as a postdoc but eventually she was appointed as a professor Water Engineering and Management, in particular Water systems. Suzanne Hulscher is leader of the department of Water Engineering and Management (WEM). This group consists of 35 persons and deals with the management of large, mainly natural, surface water bodies, such as rivers, estuaries and seas. In this research two distinct lines of investigation can be distinguished: one the physics of water systems, the second analysis of the management of such systems. Most of her own scientific work is related to seabed morphology. At this mo ent, 15 PhD-students are working in the group of Prof. Hulscher.

The Global Energy and Water Cycle: a brief overview of Organisations, Projects and Earth Observation Systems and Data in this Field

Dr. Peter van Oevelen, ESA/GEWEX

Thursday 24th March 2005

With the official release of the 10 year implementation plan of GEOSS (Global Earth Observation System of Systems) a next step has been taken in observation of the earth in particular for the processes related to the Energy and Water Cycle. For many scientists the acronym soup of organizations and projects is an incomprehensible jungle with no clear purpose or meaning. In this short presentation I will try to shed some light in the structure and objectives of the various organizations and projects and their relationships. Furthermore, I will try to give some practical entries to show the usefulness of these projects, how they operate and why contributions to and participitation in these projects is so valuable. I will conclude with a short overview on obtaining and requesting data from ESA and how to use the internet to obtain the necessary information.

Peter J. van Oevelen has obtained his MSc (1991) and PhD (2000) from Wageningen University. At the same university he has been a lecturer until 2004. In 2000 he co-founded SarVision a company that works in the area of Earth Observation for the Natural Environment with an emphasis on applications of radar remote sensing in tropical rainforests. In 2004 he left SarVision to start working for the European Space Agency and the Global Energy and Water Cycle Experiment (GEWEX) as European coordinator. His current research interests are remote sensing applications in hydrology in particular microwave remote sensing (both active and passive), climate and global change research.

Advances in four-stream radiative transfer and applications

Dr. Wout Verhoef, NLR

Thursday 17th February 2005

Radiative transfer models for soils, leaves, vegetation canopies and the atmosphere can be used for the quantitative and physically-based interpretation of remote sensing data. Four-stream models can be applied to a wide variety of media, are fast and allow the flexible and modular construction of multilayered ensembles by means of the "adding" method.
Recent versions of the SAIL canopy reflectance model are numerically robust, speed-optimized, and include 3-D phenomena like leaf shadowing and crown clumping. Applications of 4-stream models are shown in the fields of mission design and preparation (SPECTRA mission), vegetation functioning (fAPAR), thermal emissivity and retrieval of geo-biophysical variables. In a GIS-modelling-RS chain simulated images are compared to actual images, and by means of feedback, object properties can be updated and refined. Here the role of prior information from the GIS database must be balanced against the retrievals from new RS images.

Wout Verhoef has been employed in remote sensing since 1973, and since 1977 he works at the National Aerospace Laboratory NLR. He developed a series of vegetation canopy reflectance models based on SAIL, and his main interest is in advanced applications of radiative transfer models in support of the quantitative analysis of optical remote sensing imagery. He has been involved in various ESA projects related to the SPECTRA Earth Explorer mission.