Assessing the Potential of Spatial SAR Data in the Biomass Proxy: A case study on agricultural fields in the Netherlands

Providing farmers with the tools to monitor their crops continuously and reliably can aid the scaling of global food production to meet the ever-growing demand. The optical Normalised Difference Vegetation Index (NDVI) is commonly used to monitor crop greenness as an indicator for biomass, but it is limited by clouds and signal saturation....

Sensitivity Assessment of Sentinel-1 SAR Closure Phase to Vegetation and Soil Moisture Dynamics: A Case Study for Regions in Southern France

From three coherent SAR images it is possible to estimate three interferograms. Combined in a circular way, the sum of the three interferometric phases is called the closure phase which necessarily adds up to zero on a single pixel level. However, if the interferograms are spatially averaged, phase consistency is not guaranteed. In most of the...

Remote sensing data as a soil moisture indicator for grass-covered dikes

Dikes hold back water and protect the land behind it from flooding. Due to rising sea levels, land subsidence and more extreme weather patterns, the function of dikes become increasingly important. To ensure dike safety, dikes are regularly inspected. With about 22,500 kilometers of dikes in the Netherlands, this is a very slow, costly and time...

Monitoring the impact of droughts on vegetation in Australia using MetOp ASCAT Dynamic Vegetation Parameters

Droughts are considered to be one of the most damaging, yet least understood, natural hazards of all. Despite their prevalence, a thorough understanding of them lacks because they are such complex phenomena, and their manifestation can differ depending on the region they occur in. Monitoring hydrological variables and processes is imperative for...

Towards climate resilient green-blue roofs: Defining the strengths and weaknesses of green-blue roofs regarding temperature management and water storage

A green-blue roof consists of a water storage layer with on top a substrate layer covered with vegetation. Due to the presence of the water storage layer, a green-blue roof is better capable of retaining heavy rain events. A movable valve makes it possible to manage the amount of water on the roof and the timing of drainage from the roof to the...

Investigating the influence of drought on Sentinel-1 C-band SAR data over agricultural crops: A study in the Netherlands

The stress on global food security is expected to increase. Hence, crop and drought monitoring will become increasingly important in the future. Synthetic Aperture Radars (SAR) are able to penetrate clouds and thus reliably provide data. Despite the extensive literature that can be found on the use of high spatio-temporal resolution SAR data, a...

Quantifying Agricultural Intensification in the US: Trends in Yield & Microwave Remote Sensing in the Midwest

Increases in crop production show increasing trends in agricultural intensification. These trends are predominant in the corn and soybean crop production of the United States' Midwest region. The increase of production and irrigation in the past 20 years is spatially diverse, with some regions in the Midwest intensifying agriculture at faster...

Investigating the MetOp ASCAT vegetation parameters

In this study, an unsupervised classification approach is used to investigate and characterize the spatial and temporal variability of MetOp-A ASCAT backscatter (σ◦) and the TUW SMR vegetation parameters across mainland France between 2007 and 2017. Currently, soil moisture data is retrieved from ASCAT backscatter measurements using the TU Wien...

Multidisciplinary Project Cotton Water: Baseline study of designing sustainable instruments for smallholders in Maharashtra, India

This report represents the baseline study of the Project "Cotton Water", a collaboration between Solidaridad Asia, TU Delft and other participating instututions to improve the livelihood of cotton farmers in the Vidarbha and Marathwada regions of Maharashtra, India. This baseline study was divided in three main steps: a desktop study, where high...

Active microwave remote sensing of the Amazon forest region

The Amazon rainforest is among the most vital ecosystems on earth, holding about a quarter of the global terrestrial carbon sink. Since 2005, three 100-year return period droughts have occurred, the likes of which have the potential to turn the forest from a carbon sink to a source – meaning disastrous consequences for the planet. Monitoring of...

Flooding observations in Rotterdam: mapping of flood-prone locations, flood vulnerability and risk analysis

This thesis focuses on identifying flood-prone locations, flood vulnerability and analyzing risk for the Municipality of Rotterdam. Municipal call center data of flooding complaints from 2012-2016 are investigated to identify the most flood-prone locations, which are called hot spots. This is performed by creating heat maps of the flooding...

Value of information on the operation of a dual-purpose reservoir

Reservoirs are often operated to meet two or more objectives that sometimes may conflict. An example of this conflict is to keep storage low enough to maintain spare capacity for flood protection, but also to keep it high enough to maintain reliability of water / hydropower supply. Optimising the control decisions of reservoirs can provide a...

Assimilation of soil moisture data with the ensemble Kalman filter for the intermediate scale soil moisture predictions in the Netherlands

This thesis discusses the applicability of assimilation of artificial SMAP data into a quasi steady state hydrological model to improve soil moisture estimates. The model used for this research was SIMGRO and since no real SMAP data were available at the time of the research, artificial SMAP data were used. The ensemble Kalman filter was used to...

Assessing the Accuracy of Water Temperature Determination and Monitoring of Inland Surface Waters Using Landsat 7 ETM+ Thermal Infrared Images

This research evaluates the potential of thermal infrared (TIR) remote sensing to determine and continuously monitor the horizontal water temperature distribution of inland surface water bodies. Usually, monitoring temporal and spatial variability of surface water temperature takes place by measurement networks of in-situ gauges, but these...

Measuring weight fluctuations in trees based on natural frequency

Satellite-based soil moisture measurements indicate a diurnal variation in backscatter in west Africa. This diurnal variation is assumed to be caused by variation of moisture content in vegetation (Friesen, 2008). The obtained satellite soil moisture data can be improved, if ground measurements support this hypothesis. Especially at locations...

Diurnal differences in vegetation dielectric constant as a measure of water stress

Currently, vegetation is considered a barrier to soil moisture retrieval by both passive and active remote sensing missions. Microwave emission and backscattering of vegetation is driven by the vegetation dielectric constant, which is a function of vegetation water content. The latter is a measure of root zone water availability. Understanding...

Data assimilation of GRACE terrestrial water storage data into a hydrological model using the Ensemble Kalman Smoother: A case study of the Rhine river basin

Terrestrial water storage (TWS) can be defined as the storage of water on and below the land surface, and includes snow, ice, surface water, soil moisture, and ground water. TWS is a key component of the terrestrial and global hydrological cycles, which have important control over the water, energy and biogeochemical fluxes, and plays a major...

A new perspective on continental moisture recycling

The importance of moisture feedback between continental precipitation and evaporation, referred to as moisture recycling, is still under debate. Most of the research in the past focused on the contribution of recycling to precipitation within a certain region only. This paper clearly distinguishes between different definitions of moisture...