Yann Chemin

The surface energy balance algorithm for land (SEBAL) has been successfully applied to estimate evapotranspiration (ET) and yield at different spatial scales. However, ET and yield patterns have never been investigated under highly heterogeneous conditions. We applied SEBAL in a salt-affected and water-stressed maize field located at the margin of...

Olive trees have been of economic and cultural value since pre-Roman times, and continue to dominate landscapes and agriculture in many mediterranean regions. Recent mass losses of olive trees in Southern Italy due to an exotic plant pathogen highlight the need for methods that to monitor the olive trees in a landscape or region operationally. Here...

The geology and mineralogy of the Apollo 12 landing site has been the subject of recent studies that this research attempts to complement from a remote sensing point of view using the Moon Mineralogy Mapper (M ³ ) sensor data, onboard the Chandrayaan-1 lunar orbiter. It is a higher spatial-spectral resolution sensor than the Clementine UVVis sensor...

This research is spearheading the integration of Free and Open Source Software (FOSS) and Open Source Hardware (OSHW) in the field of agri-meteorology applications to disaster risk reduction, flood and droughts. A Do-It-Yourself weather station based on OSHW standards has been developed from local sources in Sri Lanka, reporting by SMS to tank/rese...

Good estimates of ecosystem complexity are essential for a number of ecological tasks: from biodiversity estimation, to forest structure variable retrieval, to feature extraction by edge detection and generation of multifractal surface as neutral models for e.g. feature change assessment. Hence, measuring ecological complexity over space becomes cr...

Monitoring water stored in lakes and reservoirs is much needed in various countries for energy generation, food security and mitigating floods, among recurrent global issues. Natural and human-made open water bodies do not all have monitoring systems, this lack of regular information generates uncertainties in modeling, and increases unaccounted ti...

The geology and mineralogy of the Apollo 12 landing site has been the subject of recent studies that this research attempts to complement from a remote sensing point of view using the Moon Mineralogy Mapper (M3) sensor data, onboard the Chandrayaan-1 lunar orbiter. It is a higher spatial-spectral resolution sensor than the Clementine UVVis sensor a...

This research is spearheading the integration of Free and Open Source Software (FOSS) and Open Source Hardware (OSHW) in the field of agri-meteorology applications to disaster risk reduction, flood and droughts. A Do-It-Yourself weather station based on OSHW standards has been developed from local sources in Sri Lanka, reporting by SMS to tank/rese...

The geology and mineralogy of the Apollo 12 landing site has been the subject of recent studies that this research attempts to complement from a remote sensing point of view using the Moon Mineralogy Mapper (M3) sensor data, onboard the Chandrayaan-1 lunar orbiter. It is a higher spatial-spectral resolution sensor than the Clementine UVVis sensor a...

The idea was initially to install a networked grid of weather instruments from locally-made open source hardware technology, on land and seas, that report live the state of climate. After initial stakeholder meetings, it was agreed to first try to connect any existing weather stations from different governmental and private sector agencies. This wo...

Geographical Information System (GIS) is known for its capacity to spatially enhance the management of natural resources. While being often used as an analytical tool, it also represents a collaborative scientific platform to develop new algorithms. Thus, it is critical that GIS software as well as the algorithms are open and accessible to anybody...

Geographical Information System (GIS) is known for its capacity to spatially enhance the management of natural resources. While being often used as an analytical tool, it also represents a collaborative scientific platform to develop new algorithms. Thus, it is critical that GIS software as well as the algorithms are open and accessible to anybody...

This research work is about finding the connection between farmers perspectives on changes of water conditions in their socio-agricultural environment and satellite remote sensing analysis. Key informant surveys were conducted to investigate localised views on water scarcity as a counterpoint to the physical measurement of water availability. Does...

Sri Lankan cities have faced severe impacts of climate change over past years. Past records of daily temperature and rainfall data reveal significant changes of temperature and rainfall patterns during last two decades. Identification of level of vulnerability plays an important role in decision making process. Local and national level institutions...

``How can I load input satellite imagery, compute an input raster into a given result and write that result as a new image to the hard disk''. This book gives a range of programming options to answer this question, using high-level and low-level programming languages, some serial (C, Python, R) but also some in parallel (OpenMP, MPI-C, CUDA, OpenCL...

Malwatu Oya basin in Northwestern Sri Lanka is subject to intense rainfall. Cascade systems of reservoirs, being interconnected are less informed about actual incoming run-off, especially with high intensity rainfall is hitting various part of the watershed. A first step to support the water management effort of the irrigation department is to inte...

Study region Increasing demographic pressure and economic development in the Mekong Basin result in greater dependency on river water resources and increased vulnerability to streamflow variations. Study focus Improved knowledge of flow variability is therefore paramount, especially in remote catchments, rarely gauged, and inhabited by vulnerable...

The rainwater harvesting network is in need of volumetric estimation of rainfall-runoff contributed to recharge of the aquifers. Regular reporting of high quality rainfall events and intensity is still a challenge to be addressed in Sri Lanka. A combination of Open Source Hardware (OSHW) and Free & Open Source Software (FOSS) is being used to creat...

The rainwater harvesting network is in need of volumetric estimation of rainfall-runoff contributed to recharge of the aquifers. Regular reporting of high quality rainfall events and intensity is still a challenge to be addressed in Sri Lanka. A combination of Open Source Hardware (OSHW) and Free & Open Source Software (FOSS) is being used to creat...

Soil erosion due to accelerating runoff in various land cover types pose a serious threat to the long term sustainability of the fragile Himalayan landscape characterized by subsistence farming. Delimitation of high runoff zones, fostering soil erosion in the agricultural dominated watersheds is thus a necessity for watershed managers, NGO’s, urban...

Coffee is the second most traded commodity in the world after oil. A sustainable coffee industry is crucial to maintaining global agriculture, trade, human and environmental well-being, and livelihoods. With increasing water scarcity and a changing climate, understanding and quantifying the risks associated with water, a primary input in coffee pro...

Human activities and movements in space have attracted considerable research interest in planning. One of the major issues in the human movement studies is data collection, which concerns the poor understanding of pedestrian spatiotemporal behavior. Most of the earliest data collection methods are based on questionnaires and observations. Later on...

Human activities and movements in space have attracted considerable research interest in planning. One of the major issues in the human movement studies is data collection, which concerns the poor understanding of pedestrian spatiotemporal behavior. Most of the earliest data collection methods are based on questionnaires and observations. Later on...

The upcoming GRASS GIS 7 release improves not only raster processing and general design but the vector processing in the first place. GRASS GIS, as a topological GIS, recognizes that the topology plays the key role in the vector processing and analysis. Topology ensures that adjacent geographic components in a single vector map are related. In cont...

Despite being necessary for effective water management, the assessment of an irrigation system requires a large amount of input data for the estimation of related parameters and indicators, which are seldom measured in a regular and reliable manner. In this work, spatially distributed surface energy balance fluxes and geographical information syste...

The actual state of the water monitoring network in Sri Lanka is limited in many ways. Few rivers are actually monitored to international standards, rainguage network is expensive to maintain, weather variable are recorded few time a day in weather stations. A comprehensive water balance monitoring for a river basin needs a dedicated network of wea...

The GRASS Image Processing Environment is an effort to improve the remote sensing capabilities of GRASS GIS within its future incarnation as in version 7. The remote sensing capacities of GRASS GIS have always been limited to the minimum, i.e. georeferencing, classification, filtering and transform. The prevailing assumption was that scripting was...

Earth monitoring of the water cycle has an ever increasing demand in space and time resolution. Evapotranspiration is by far the most important quantity of water in a water balance, making its measurement of paramount importance. Evapotrasnpiration modeling has now become widely established as a specialized field at the meeting points of thermodyna...

Availability of rainfall time-series is limited in many parts of the World, and the continuity of such records is variable. This research endeavors to extend actual daily rainfall observations to ungauged areas using vegetation response as witnessed by remote sensing data and taking into account rainfall event histograms as well as cumulative total...

This research expands on the continuous collection of ground truth data to feed in various empirical relationships enabling the calibration of a simple two source energy balance in order to provide with instantaneous remote sensing based ET in an irrigated area of Murray Darling Basin under Australian conditions. Standard satellite remote sensing T...

Rice submergence is the condition by which the water level rises above the rice canopy. In general, rice plant response to submergence is to elongate its shoots above the rising water level. This costs energy and eventually has a direct impact in terms of reducing yield. A specific gene, called Sub1, when introgressed into popular rice varieties by...

Monitoring of water and land objects enters a revolutionary age with the rise of ubiquitous remote sensing and public access. Earth monitoring satellites permit detailed, descriptive, quantitative, holistic, standardized, global evaluation of the state of the Earth skin in a manner that our actual Earthen civilization has never been able to before....

Rice submergence is the condition by which the water level rises above the rice crop canopy. In general, rice plant response to submergence is to elongate its shoots above the rising water level. This costs in energy and eventually has a direct impact in terms of reducing yields. A specific gene, called Sub1, when introgressed into popular rice var...

Availability of rainfall time-series is limited in many parts of the World, and the continuity of such records is variable. This research endeavors to extend actual daily rainfall observations to ungauged areas, taking into account events of rainfall as well as cumulative total daily rainfall, over a period of 11 years. Results show that rainfall e...

Information on the exact location of rice production, and the crop yield in those areas, is important for developing location-specific technologies that address yield limiting factors. We are developing an automated system for mapping rice paddies that use multitemporal MODIS sensor satellite images. MODIS images are freely available. The temporal...

Faced with unreliable rainfall patterns, Australian farmers have developed on-farm water storage (OFS) solutions over the drought years. Recent thinking in water policy under the Commonwealth government considers extending the Cap over surface water to OFS as they are not currently covered under the Cap and eluded the effective water policy arrange...

On the Australian continent, approximately 90% of the precipitation that falls on the land is returned back to the atmosphere through actual evapotranspiration (ET a). However, it is almost impossible to measure it directly at a meaningful scale in space and time through traditional methods. Since the late 1990s, numerous algorithms have been devel...

Hydrological knowledge of irrigated farms within the inundation plains of the Murray-Darling Basin (MDB) is very limited in both quality and reliability of the observation network. This paper focuses on Land Surface Diversions (LSD) that encompass all forms of surface water diversion, except the direct extraction of water from rivers, watercourses...

Irrigated agriculture is major consumer of fresh water, but a large part of the water devour for irrigation is wasted due to poor management of irrigation systems. Improving water management in irrigated areas require the analysis of real time water demand in order to determine the possibilities in which it may be modified and rationalised. Real ti...

In the northern catchments of the Murray Darling Basin of Australia, a significant proportion of total water diversions are from interception of floodwater and overland flow during sporadic storm events. These diversions (known as Land Surface Diversions or LSD) prevent runoff from entering natural watercourses or into the floodplain. Due to advers...

Recent drought in Australia and concerns about climate change have highlighted the need to manage agricultural water resources more sustainably, especially in the Murray Darling Basin which accounts for more than 70% of water for crop production. For Australian continent, approximately 90% of the precipitation that falls on the land is returned bac...

Hydrological knowledge of irrigated farms within the inundation plains of the Murray Darling Basin (MDB) is very limited in quality and reliability of the observation network that has been declining rapidly over the past decade. This paper focuses on Land Surface Diversions (LSD) that encompass all forms of surface water diversion except the direct...

Rice plays a major role in the global supply and demand for sustainable food production. The constraints of maintaining sustainable rice production are closely linked to the relationship between the distribution patterns of human activity on the planet and economic growth. Global patterns of rice production can be mapped by using various criteria l...

Agricultural use is by far the largest consumer of fresh water worldwide, especially in the Mediterranean, where it has reached unsustainable levels, thus posing a serious threat to water resources. Having a good estimate of the water used in an agricultural area would help water managers create incentives for water savings at the farmer and basin...

Crop Assimilation Model (CAM) predicts the parameters of agrohydrological models with satellite images. CAM with double layers GA called CAM-DLGA, uses Soil-Water-Atmosphere-Plant (SWAP) agro-hydrological model and Genetic Algorithm (GA) to estimate inversely the model parameters. In CAM-DLGA, initially the GA parameters are required to set in adva...

Estimating agricultural water use is an issue of primary importance in the Mediterranean. At the same time, several advanced algorithms have been developed, which couple Earth Observation data in thermal, visible and near-infrared wavelengths with a few meteorological measurements to provide a close approximation to the actual water use. However, d...

Vegetation Index Map provides the crop density information over a precise region. Remote Sensing (RS) images are at the basis of creating such map, while the decision-maker requirement stands for Vegetation Index Maps at various in-country administrative levels. However, RS image includes data noises due to influence of haze or cloud especially in...

Vegetation Index Map provides the crop density information over a precise region. Remote Sensing (RS) images are at the basis of creating such map, while the decision-maker requirement stands for Vegetation Index Maps at various in-country administrative levels. However, RS image includes data noises due to influence of haze or cloud especially in...

Remote Sensing (RS) provides images over large areas such as provincial or country level.During the last 20 years, it plays a vital role for developing many complex applications. However, RSimage includes data noises due to influence of haze or cloud especially in the rainy season. It is thusnecessary to remove the noise to recover the real ground...

An agro-hydrological simulation model is useful for agriculture monitoring. One issue inrunning such model is parameter identification, especially when the target area is large such asprovincial or country level. Remote Sensing (RS) provides us with useful information over large area.RS cannot observe input parameters of agro-hydrological models di...

Monitoring of water consumption in irrigation systems has become increasingly important for water managers in the actual trend of integrated water management. Low spatial resolution (LSR) satellite remote sensing has already proven the capacity of monitoring evapotranspiration (ETa) over large areas at high temporal frequencies, by which monitoring...

Remote Sensing (RS) provides images over large areas such as provincial or country level. During the last 20 years, it plays a vital role for developing many complex applications. However, RS image includes data noises due to influence of haze or cloud especially in the rainy season. It is thus necessary to remove the noise to recover the real grou...

Agricultural monitoring is indispensable for competent food security management that involves forecast, management, and monitoring. A simulation model SWAP (Soil, Water, Atmosphere, and Plant) has been utilized for these purposes. SWAP is equipped with crop models and water management modules where the growth and development of a crop can be simula...

Satellite image processing plays a vital role for research developments in Astronomy, Remote Sensing, GIS, Agriculture Monitoring, Disaster Management and many other fields of study. However, processing those satellite images requires a large amount of computation time due to its complex and large processing criteria. This seems a barrier for real...

Increasing water scarcity in the downstream areas of several river basins demands improved water management and conservation in the upper reaches. Improved management is impossible without proper monitoring at various levels. In the Aral Sea Basin, monitoring is carried out, albeit largely by under-paid staff; however, the water flows to farms and...

Agricultural monitoring is necessary for efficient food security management at country level. The near real time monitoring or prediction on crop growth in terms of planting date, acreage, planting intensity, water stress, biomass, yield and etc. is important. It can contribute to better policymaking, timely countermeasures, optimization of water r...

A method is proposed to optimize the input parameters of a one-dimensional crop model (SWAP) by assimilating simulated evapotranspiration with remote sensing data. The optimization is based on GA (Genetic Algorithm). However it requires huge computation time, which is one of the constraints for practical implementation of the method. This paper add...

GRASS GIS (Geographical Resources Analysis Support System) is a free, open source software and has been used for Remote Sensing (RS) and Geographic Information System (GIS) data analysis and visualization. Inside GRASS, different modules have been developed for processing satellite images. Currently, GRASS uses databases to handle large datasets an...

Efforts aimed at improving regional water management are often frustrated due to the paucity of reliable and consistent information. This paper assesses the scope for remote sensing information, freely available on the Internet, to help water managers in obtaining reliable and consistent information at large (sub) system level. In the Ferghana prov...

Recently, advances have been made to obtain estimates of evapotranspiration (ET) through remote sensing. A problem still persists to get ET over a longer time period. Orbiting satellites supply with images answering the need for water consumption data, but due to technical limitations have either high spatial resolution restricted to low revisit fr...

Water resources planning depends on the physical environments, notably on the vegetation and hydrological conditions in river basins. Vegetation growth—both natural and human induced—has a strong dynamic behavior which, especially at larger scales, is difficult to survey in the field. Low cost imagery from the NOAA–AVHRR satellite provides new oppo...

The irrigated Indus Basin in Pakistan has insufficient water resources to supply all its stakeholders. Information on evaporative depletion across the Basin is an important requirement if the water resources are to be managed efficiently. This paper presents the Surface Energy Balance Algorithm for Land (SEBAL) method used to compute actual evapotr...

Estimation of crop water deficit continues to be challenging especially when attempting to evaluate it at large areas. The limitation of cloud free images availability can be overcome with the combination of high-spatial and temporal resolution images in the tropical climate. In this study, Landsat 7 & MODIS satellites Image on the same overpass da...

Sri Lanka does not have a prior experience in preparing a National Physical Planning for its integrated development. The National Physical Planning Department has not only setup a GIS Laboratory to cater to National Physical Planning of Sri Lanka, but it also ventured into acquiring a full Landsat 7 ETM+ coverage of the Island for 1999-2001 in the...

Limited availability of freshwater and increasing demand for food require careful management of available resources. However, information on water utilization within river basins is often inadequate for comprehensive water management. Therefore, researchers are developing new tools and methodologies to overcome these data problems. A major concern...

The quality of decision making in water resources management is proportionally dependent on the quality (reliability, standardization, spatial and temporal dimensions) of the information pertaining to water fluxes into the unit managed, may it be an irrigation system, an administrative unit or an hydrological (sub)basin. The availability of publicl...

This study uses the images from the Corona ìspyî satellite, which have been declassified in November 2002 and available on Internet order for a very low cost. The image used dates from 1973 and has about 6m panchromatic characteristics. Along with a Landsat5TM of 1990 and Aster of 2001, a temporal range of about 30 years is achieved. A simple class...

This paper proposes a method to run SWAPDLGA with automatic generation of suitable GA parameters. The proposed method computes the suitable GA parameters using the Parameter-less GA (PLGA)3) and runs SWAPDLGA with the computed GA parameters. Both SWAP-DLGA and PLGA require huge computational time. This paper also presents implementation of the prop...

A common understanding of the movement of groundwater recharge by rainwater harvesting that occurred for the last decades leads to the belief that it had a significant positive impact on the vegetation of Gujarat, to the least in areas having crops irrigated by groundwater. Using the historical remote sensing data publicly available from the Intern...

One of the difficulties currently facing remote sensing scientists is the technical limitations of Earth Observation satellites, when trying to provide regular and fine resolution information about the water consumption of crops in irrigation systems. The solution could be to combine satellite images from various sources, some of high spatial resol...

"Amongst the most crucial information in water balance assessment, is the evapotranspiration (ET) of the plants, especially field crops. A large literature is available on potential and reference ET, and it is a modeling exercise to assess the crop areas, the level of effective development and the water stress found under the presupposed field cond...