UCL University College London Eprints
UCL Eprints collects the work of UCL researchers and makes it freely available over the web, helping the worldwide scholarly community to discover UCL research. Institutional repositories like UCL Eprints complement the traditional academic publishing and scholarly communications processes. They raise the visibility of research and help to maximise its impact. UCL researchers are encouraged to deposit a copy of each journal article, conference paper, working paper, and any other research output, in the UCL Eprints at the earliest opportunity, ensuring that their research reaches as wide an audience as possible.
Automated stereo retrieval of smoke plume injection heights and retrieval of smoke plume masks from AATSR and assessment with CALIPSO and MISR. - Fisher, D; Muller, JP; Yershov, V
The longevity and dispersion of smoke and asso- ciated chemical constituents released from wildfire events are dependent on several factors, crucially including the height at which the smoke is injected into the atmosphere. The aim here is to provide improved emission data for the initialization of chemical transport models in order to better predict aerosol and trace gas dispersion following injection into the free atmosphere. A new stereo-matching algorithm, named M6, which can effec- tively resolve smoke plume injection heights (SPIH), is presented here. M6 is extensively validated against two alternative space- borne earth observation SPIH data sources and demonstrates...
Sensor Intercalibration Over Dome C for the ESA GlobAlbedo Project - Potts, D; Mackin, S; Muller, J; Fox, N
The response of a variety of Earth observation satellite sensors from multiple platforms, as well as different sensors on the same platform, were cross-compared over Dome C in Antarctica. A single unified methodology was employed to remove geometric, temporal, and atmospheric biases between different sensors with a range of spatial resolutions, bandwidths, and overpass times. The result assumes no “correct” baseline value, only relative responses. The resulting responses of the sensors, namely, AATSR, MERIS, and VEGETATION 2, are here presented and, where overlap occurs, compared with the results from other groups. In addition to applying the Quality Assurance for Earth...
Multi-resolution digital terrain models and their potential for Mars landing site assessments - Kim, J; Lin, S; Muller, J; Warner, N; Gupta, S
One of the key issues for planetary, especially Mars surface exploration, is how to make an objective assessment of criteria for landing sites selection for future rovers, sample return missions and landers considering topographic variables such as slope, altitude and roughness as well as their physical scattering properties. For these purposes, stereo vision analysis is here proposed as the best possible solution to provide reliable topographic data. Recently, a number of successful orbital missions to Mars have taken place including the Mars Express mission with the High Resolution Stereo Camera (HRSC) as well as the Mars Reconnaissance Orbiter spacecraft equipped...
Global warping coefficients for improving ATSR co-registration - Fisher, D; Muller, J
Globally applicable warping coefficients for improving the co-registration between the forward and nadir views of the series of Along-Track Scanning Radiometer (ATSR) instruments are presented. The coefficients are derived from a polynomial- based warp, using a least squares fit on a set of automatically detected forward to nadir tie points. In-depth statistical analysis is presented here covering both an independent analysis of the warping coefficients using the Pyramidal-Gotcha algo- rithm and a global assessment using the Speeded Up Robust Features tie-pointing algorithm. This independent assessment shows that the co-registration between the nadir and forward views improves in all cases to...
New products for a better characterisation of smoke plume and gas/aerosol dispersion from boreal eurasian forest fires: the ALANIS Smoke Plume project - Muller, JP; Yershov, V; Fisher, D; Krol, M; Peters, W; San-Miguel, J; Palumbo, I; Sedano, F; Strobl, P; Clerbaux, C; George, M; Helbert, J; Guillaume, B
The ALANIS (Atmosphere-LANd Integrated Study) Smoke Plume project is an on-going study funded by the ESA's Support to Science Element (STSE) dedicated to the monitoring of the fire aerosol and trace gases dispersion over Eurasia from multi-mission EO-based data, in link with the scientific issues of land-atmosphere processes in the iLEAPS community. The injection and dispersion of the smoke plumes are performed with the TM5 model from several new products (burnt areas and forest fire emissions amounts, smoke plumes injection heights) derived from the MERIS and AATSR products and from the validated IASI CO products. A first study focused on...
Hesperian equatorial thermokarst lakes in Ares Vallis as evidence for transient warm conditions on Mars - Warner, N; Gupta, S; Kim, JR; Lin, SY; Muller, JP
On Earth, permafrost thawing is linked to climate warming. Similarly, on Mars, permafrost degradation, described from mid-latitude and equatorial settings, is likely linked to global or regional climate change. Putative thermokarst depressions identifi ed on Mars are widely considered to be the result of sublimation, evaporation, or thawing of an ice-rich substrate. The possibility that the depressions formed by melting of permafrost to create alas-like lakes has been recently proposed, but is controversial, owing to the lack of primary evidence for liquid fi lling the depressions. Here we use high-resolution Mars Reconnaissance Orbiter Context Camera images and derived topographic data...
'Region-growing' algorithm for matching of terrain images - Otto, GP; Chau, TKW
The paper describes and discusses a new algorithm for stereo matching, which has been designed to work well with data from the SPOT satellite1. It is basically an extension of Gruen's adaptive least squares correlation algorithm2.3, so that whole images can be automatically matched, instead of just selected patches. Initial results on the quality of results are presented and discussed, together with a theoretical analysis of the potential speed on both conventional and multiprocessor architectures, and a brief discussion of the running speeds achieved. In addition, a method for assessing the accuracy of the matching without using any external reference...