Simulation of the formation and propagation of the thermal bar on Lake Ontario

Computer-based, mathematical models that simulate spatially distributed and time dependent environmental processes are increasingly recognized to provide diagnostic and productive outputs for the assessments of environmental factors. Mathematical models have been utilized since 60's to study the water quality, the circulation structure and the seasonal changes of large water bodies such as the Great Lakes. Analysis of changes in water quality related to seasonal cycles such as the formation and the propagation of the thermal bar requires spatial and temporal models, with high resolution. The overall objective of this study was to integrate geo-referenced site-specific spatial data to a 3D hydrodynamic model (ALGE) and compare the outputs with geo-referenced remotely sensed thermal imagery. The motivation of this work is based on the idea that the spatial data provides a significant advantage of equipping the model with site-specific data to manipulate site-specific circulation patterns. Further, since the input is geo-referenced and site-specific, the output can be directly compared to geo-referenced remotely sensed imagery for model validation. Thus, the aspect of the integration of spatial data to hydrodynamic models is an obvious and promising approach to study lake-wide hydrodynamic processors and seasonal changes. A specific objective of the study was to examine how different spatial patterns and weather conditions influence the formation and the propagation of the thermal bar temporally and spatially. Several preliminary studies were conducted on square lakes and lakes with false bathymetric profiles, and compared with the results of laboratory studies and field surveys. Since the outputs compared well with the literature, bathymetric data of Lake Ontario was integrated to the 3D hydrodynamic model with real time surface and atmospheric weather data. The formation and the propagation of the thermal bar was simulated for the years 1997, 1998, 1999 and 1997 (winter) through 1998(fall). The model was finetuned by changing the initial conditions and weather data to obtain a good approx imation to the surface temperature derived from satellite imagery using the split and dual window technique. The lake was also subjected to different weather conditions to study its influences on the formation and propagation of the thermal bar. The model outputs from case studies as well as comparisons of the model output with satellite imagery and the NOAA forecasting model are discussed

Enhanced change detection index for disaster response, recovery assessment and monitoring of buildings and critical facilities-A case study for Muzzaffarabad, Pakistan

The availability of Very High Resolution (VHR) optical sensors and a growing image archive that is frequently updated, allows the use of change detection in post-disaster recovery and monitoring for robust and rapid results. The proposed semi-automated GIS object-based method uses readily available pre-disaster GIS data and adds existing knowledge into the processing to enhance change detection. It also allows targeting specific types of changes pertaining to similar man-made objects such as buildings and critical facilities. The change detection method is based on pre/post normalized index, gradient of intensity, texture and edge similarity filters within the object and a set of training data. More emphasis is put on the building edges to capture the structural damage in quantifying change after disaster. Once the change is quantified, based on training data, the method can be used automatically to detect change in order to observe recovery over time in potentially large areas. Analysis over time can also contribute to obtaining a full picture of the recovery and development after disaster, thereby giving managers a better understanding of productive management and recovery practices. The recovery and monitoring can be analyzed using the index in zones extending from to epicentre of disaster or administrative boundaries over time.EU FP

Enhanced change detection index for disaster response, recovery assessment and monitoring of accessibility and open spaces (camp sites)

The availability of Very High Resolution (VHR) optical sensors and a growing image archive that is frequently updated, allows the use of change detection in post-disaster recovery and monitoring for robust and rapid results. The proposed semi-automated GIS object-based method uses readily available pre-disaster GIS data and adds existing knowledge into the processing to enhance change detection. It also allows targeting specific types of changes pertaining to similar man-made objects. This change detection method is based on pre/post normalized index, gradient of intensity, texture and edge similarity filters within the object and a set of training data. Once the change is quantified, based on training data, the method can be used automatically to detect change in order to observe recovery over time in large areas. Analysis over time can also contribute to obtaining a full picture of the recovery and development after disaster, thereby giving managers a better understanding of productive management practices.EU FP

Case studies on data-rich and data-poor countries

The aim of Work Package 5 is to assess the needs of decision-makers and end-users involved in the process of post-disaster recovery and to provide useful guidance, tools and recommendations for extracting information from the affected area to help with their decisions. This report follows from Deliverables D5.1 “Comparison of outcomes with end-user needs” and D5.2 “Semi-automated data extraction” where the team had set out to explore the needs of decision-makers and suggested protocols for tools to address their information requirements. This report begins with a summary of findings from the scenario planning game and a review of end-user priorities; it will then describe the methods of detecting post-disaster recovery evaluation and monitoring attributes to aid decision making. The proposed methods in the deliverables D2.6 “Supervised/Unsupervised change detection” and D5.2 “Semi-automated data extraction” for use in post-disaster recovery evaluation and monitoring are tested in detail for data-poor and data-rich scenarios. Semi-automated and automated methods of finding the recovery indicators pertaining to early recovery and monitoring are discussed. Step-by-step guidance for an analyst to follow in order to prepare the images and GIS data layers necessary to execute the semi-automated and automated methods are discussed in section 2. The outputs are presented in detail using case studies in section 3. In order to develop and assess the proposed detection methods, images from two case studies, namely Van in Turkey and Muzaffarabad in Pakistan, both recovering from recent earthquakes, have been used to highlight the differences between data-rich and data-poor countries and hence the constraints on outputs on the proposed methods

Supervised / unsupervised change detection

The aim of this deliverable is to provide an overview of the state of the art in change detection techniques and a critique of what could be programmed to derive SENSUM products. It is the product of the collaboration between UCAM and EUCENTRE. The document includes as a necessary requirement a discussion about a proposed technique for co-registration. Since change detection techniques require an assessment of a series of images and the basic process involves comparing and contrasting the similarities and differences to essentially spot changes, co-registration is the first step. This ensures that the user is comparing like for like. The developed programs would then be used on remotely sensed images for applications in vulnerability assessment and post-disaster recovery assessment and monitoring. One key criterion is to develop semi-automated and automated techniques. A series of available techniques are presented along with the advantages and disadvantages of each method. The descriptions of the implemented methods are included in the deliverable D2.7 ”Software Package SW2.3”. In reviewing the available change detection techniques, the focus was on ways to exploit medium resolution imagery such as Landsat due to its free-to-use license and since there is a rich historical coverage arising from this satellite series. Regarding the change detection techniques with high resolution images, this was also examined and a recovery specific change detection index is discussed in the report

Discovery and analysis of Gamma Doradus type pulsations in the F0 IV star HR 2740=QW Pup

We present multi-site photometric observations of the F0 IV star HR 2740=QW Pup that reveal it to be a γ Dor type variable pulsating with four frequencies: 1.0434, 0.9951, 1.1088 and 0.9019 d-1. These data were obtained at the European Southern Observatory and the South African Astronomical Observatory over a time baseline spanning from 1997 January 14 to February 11. The 1.0434-d-1 term dominates in amplitude (10 mmag) over the other three (each less than 5 mmag); the light curve comprising these four frequencies seems to be very stable and no residual power is left in the power spectrum. During the analysis particular attention was paid to methodological aspects, which cannot be neglected considering the proximity of the frequencies to 1 d-1. Physical parameters were also derived for all the well-known γ Dor stars, confirming that this class is very homogenous. In the framework of the campaign, two Ap stars (OU Pup�HR 2746 and PR Pup�HR 2761) were also observed. The photometric differences between these rotating variables and HR 2740 are emphasized, corroborating the pulsational nature of the γ Dor stars. It is further demonstrated that the rotational splitting cannot be a suitable explanation of the observed frequency content of HR 2740. © 1997 RAS

Environmental context and contaminant biotransport by Pacific salmon interact to mediate the bioaccumulation of contaminants by stream-resident fish

1. The extent to which environmental context mediates the uptake of biotransported contaminants by stream-resident organisms is not understood. For example, there is no clear understanding of the extent to which contaminant type, instream characteristics, or resident fish identity interact to influence the uptake of contaminants deposited by Pacific salmon (Oncorhynchus spp.) during their spawning runs. 2. To address this uncertainty, we sampled four stream-resident fish species from 13 watersheds of the Laurentian Great Lakes in locations with and without salmon across a gradient of instream and watershed characteristics. We determined the polychlorinated biphenyl (PCB) and mercury (Hg) concentration along with the stable isotope ratio of C and N for each stream-resident fish. 3. We found that stream-resident fish PCB concentrations were 24-fold higher in reaches with salmon and were positively related to δ15N. In contrast, stream-resident fish Hg concentrations were similar or lower in reaches with salmon and either exhibited a negative or no relationship with δ15N. 4. Based upon AICc, stream-resident fish exhibited species-specific PCB concentrations that were positively related to salmon PCB flux. Hg burdens exhibited an interaction between fish length and salmon Hg flux – as salmon Hg inputs increased, Hg levels decreased with increasing resident fish length. We found no support for models that included the mediating influence of instream or watershed factors. Salmon eggs are enriched in PCBs but have very low Hg concentrations, so our results may be driven by the consumption of salmon eggs by stream-resident fish. 5. Synthesis and applications. Our results highlight that contaminants bioaccumulate differently depending on contaminant type, species identity, and the trophic pathway to contamination. Consequently, consideration of the recipient food web and route of exposure is critical to understanding the fate of biotransported contaminants in ecosystems. The transfer of contaminants by migratory organisms represents an understudied stressor in ecology. Effective management of biotransported contaminants will require the delineation of “hot-spots” of biotransport and implementation of best management practices in those watersheds that receive contaminants from spawning salmon

Assessing the progress of river restoration in the UK: has biophysical condition improved over two decades of intervention?

Biophysical condition is one indicator of the immediate success of efforts to restore degraded rivers as well as longer-term progress towards improving water quality. In the context of the Water Framework Directive (WFD), the biophysical condition of river systems in the UK also reflects how well international environmental policy translates into improved river management domestically. We assess whether the condition of river systems in the UK has improved or declined over the past two decades, whether regions identified by the first WFD assessment have improved or declined, and thus, how effectively international policy has been implemented nationally. Methods include: statistical and spatial analysis of more than 25,000 habitat condition records collated in the River Habitat Survey over the 1990s and 2000s; computing of an Index of Change for Local Authorities; and comparison of Indices of Change with a sub-sample of 1,727 WFD assessments conducted in 258 Local Authorities. Findings include that three of four measures indicate that biophysical quality has declined, although only decline in one measure (habitat quality) was statistically significant. Riparian quality has improved, although measures do not consider invasive compared to native coverage. In total, 27 regions were identified with the worst declining quality. Comparative analysis of regions suggest that condition has declined most substantially in regions that were previously in ‘good’ condition. Priorities for future investment include improving degraded sites, protecting high quality sites, and increasing monitoring of ‘data poor’ regions. Our methodology offers an approach for utilising ‘messy’ routinely collated data like the RHS. However, guidelines are needed to support the use of similar datasets for the international river restoration community

JAE_Gerig_Dryad_Data

JAE_Gerig_Dryad_Dat