Summary The proposal is primarily a theoretical project aimed at resolving several of the most important outstanding problems associated with a promising type of cryogenic detector, the superconducting Transition Edge Sensor (TES), which offers unique capabilities far exceeding that of traditional semiconductor technology. Over the past decade TES-based detectors have found application in diverse areas from dark matter searches, X-ray astrophysics, time-resolved X-ray absorption spectroscopy, quantum information processing, biological sensors, industrial material analysis and homeland security. Practical instruments require a complex optimization of speed, linearity, energy resolution and array size. However, lack of understanding of the superconducting transition in TESs limits our ability to optimise performance and predict the behaviour of a new detector designs. The present models of TESs have played an important role during a period of extensive development of technology. However, based on empirical observations the models lack knowledge of the fundamental details of superconductivity, which determine the transition, and ultimately the performance of TESs. They cannot explain the observable energy resolution, and such fundamental properties as recently-discovered weak superconductivity of TESs. As a result, the current development path of TES detector for a certain applications is still very time consuming and costly, being in many aspects based on trial and error. Significant advances are expected if better understanding of the fundamental physics of TESs is achieved, because this would underpin accurate and streamlined design processes, leading to shorter periods of experiments with targeted design options. The project aims to develop new a theoretical model of the resistive transition in TESs based on fundamental superconductivity theory. The objectives are: 1. Understanding the mechanisms of the resistive transition in TESs as spatially inhomogeneous superconducting systems, simulating electrical and thermal fluctuations, which determine the energy resolution of TES micro- and nano- calorimeters and noise performance of bolometers 2. Developing a model of non-local energy transport in multilayered TES structures, including energy escape and fluctuations over the extremely short time scale of energy deposition and down-conversion. 3. stimulating the development of the next generation of high-performance TESs by evaluating the potential of graphene and few-layer boron nitride for engineering the coupling to a thermal bath and shaping the resistive transition An expected outcome of this project is a new approach to complex optimization of speed, linearity, energy resolution and array size for individual applications. A few examples illustrate the potential impact. An improvement of the energy resolution of TES-based soft X-ray detectors below 2 eV will allow the Athena X-ray mission proposal to ESA to study turbulence in the hot gas of clusters of galaxies, and will also allow the mapping of chemical shifts in X-ray fluorescence signals in Transmission Electron Microscopy (TEM), thus opening exciting possibilities for Industrial Materials Analysis. An increase in the number of pixels per array would lead to efficient imaging on a future X-ray telescope, and also provides the ability to sustain higher flux levels in emerging synchrotron applications, such as time-resolved X-ray spectroscopy. With several potential markets for high-resolution X-ray spectroscopy equipment, most notably synchrotron facilities and manufacturers of TEM equipment, the emergence of new companies is a likely consequence. For gamma-ray and neutron spectroscopy, larger arrays of TES detectors with higher energy resolution imply more efficient and faster screening, facilitating assessment tasks in such fields as non-destructive assay of spent nuclear fuel, and the operational detection of nuclear materials.

There are around 304 million lakes globally. These provide essential resources for human survival and are an important component of global biogeochemical cycles. Lakes are also fragile systems that are sensitive to multiple pressures including nutrient enrichment, climate change and hydrological modification, making them important 'sentinels' of environmental perturbation. However, traditional monitoring has only produced data from a tiny fraction of the global population of lakes and disentangling the causes of change requires consistently-produced data from a large number of lakes, along with measurements of possible causes of change. Satellite observations (remote sensing) and the establishment of a global lake observatory would produce a step-change in our ability to detect and attribute the causes of changes in lakes world-wide. This is now possible for three reasons: (1) the improved wavebands, spatial resolution and frequency of data collection from satellite sensors is now sufficient to monitor inland waters; (2) formulae to correct for atmospheric properties and to convert the detected reflected light to useful lake properties have been developed; and (3) computing power has increased to the point that allows near real time and archived information from satellites to be processed. GloboLakes will analyse 20 years of data from more than 1000 large lakes across the globe to determine 'what controls the differential sensitivity of lakes to environmental perturbation'. This is an ambitious project that is only possible by bringing together a consortium of scientists with complementary skills. These include expertise in remote sensing of freshwaters and processing large volumes of satellite images, collation and analysis of large-scale environmental data, environmental statistics and the assessment of data uncertainty, freshwater ecology and mechanisms of environmental change and the ability to produce lake models to forecast future lake conditions. The eight objectives of GloboLakes are to: (i) develop remote sensing algorithms to estimate lake biogeochemical and physical parameters; (ii) make these algorithms operational and process satellite data; (iii) compile integrated spatio-temporal information on climatic and catchment data for >1000 lakes; (iv) integrate data and assess uncertainty in data sources; (v) detect spatial and temporal patterns in lake water quality; (vi) attribute the causes of lake response to environmental conditions; (vii) forecast lake sensitivity to environmental change; (viii) apply data to lake management and the monitoring of freshwater resources. The project will focus on the retrieval of surface water temperature as this has a fundamental effect on lake ecology, the concentration of coloured dissolved organic matter and suspended solids that derive largely from the catchment, the abundance of phytoplankton measured as the concentration of the pigment, chlorophyll a, and the abundance of cyanobacteria (blue-green algae) that can potentially be toxic. Knowledge of the conditions of lakes and their sensitivity to change is also extremely valuable for the management of lakes and reservoirs and GloboLakes will provide information and products specifically for environmental managers. A satellite due to be launched during the course of the project, called Sentinel 2, will provide even greater spatial resolution allowing data to be collected and exploited from even smaller lakes. This will be investigated by GloboLakes and incorporated into the framework of a global lake observatory.