Applications of Satellite Earth Observations section - NEODAAS: Providing satellite data for efficient research

The NERC Earth Observation Data Acquisition and Analysis Service (NEODAAS) provides a central point of Earth Observation (EO) satellite data access and expertise for UK researchers. The service is tailored to individual users’ requirements to ensure that researchers can focus effort on their science, rather than struggling with correct use of unfamiliar satellite data

Satellite monitoring of harmful algal blooms (HABs) to protect the aquaculture industry

Harmful algal blooms (HABs) can cause sudden and considerable losses to fish farms, for example 500,000 salmon during one bloom in Shetland, and also present a threat to human health. Early warning allows the industry to take protective measures. PML's satellite monitoring of HABs is now funded by the Scottish aquaculture industry. The service involves processing EO ocean colour data from NASA and ESA in near-real time, and applying novel techniques for discriminating certain harmful blooms from harmless algae. Within the AQUA-USERS project we are extending this capability to further HAB species within several European countries

Polarimetric Synthetic Aperture Radar

This open access book focuses on the practical application of electromagnetic polarimetry principles in Earth remote sensing with an educational purpose. In the last decade, the operations from fully polarimetric synthetic aperture radar such as the Japanese ALOS/PalSAR, the Canadian Radarsat-2 and the German TerraSAR-X and their easy data access for scientific use have developed further the research and data applications at L,C and X band. As a consequence, the wider distribution of polarimetric data sets across the remote sensing community boosted activity and development in polarimetric SAR applications, also in view of future missions. Numerous experiments with real data from spaceborne platforms are shown, with the aim of giving an up-to-date and complete treatment of the unique benefits of fully polarimetric synthetic aperture radar data in five different domains: forest, agriculture, cryosphere, urban and oceans

Arctic sea ice trafficability: new strategies for a changing icescape

Thesis (Ph.D.) University of Alaska Fairbanks, 2017Sea ice is an important part of the Arctic social-environmental system, in part because it provides a platform for human transportation and for marine flora and fauna that use the ice as a habitat. Sea ice loss projected for coming decades is expected to change ice conditions throughout the Arctic, but little is known about the nature and extent of anticipated changes and in particular potential implications for over-ice travel and ice use as a platform. This question has been addressed here through an extensive effort to link sea ice use and key geophysical properties of sea ice, drawing upon extensive field surveys around on-ice operations and local and Indigenous knowledge for the widely different ice uses and ice regimes of Utqiaġvik, Kotzebue, and Nome, Alaska. A set of nine parameters that constrain landfast sea ice use has been derived, including spatial extent, stability, and timing and persistence of landfast ice. This work lays the foundation for a framework to assess and monitor key ice-parameters relevant in the context of ice-use feasibility, safety, and efficiency, drawing on different remote-sensing techniques. The framework outlines the steps necessary to further evaluate relevant parameters in the context of user objectives and key stakeholder needs for a given ice regime and ice use scenario. I have utilized this framework in case studies for three different ice regimes, where I find uses to be constrained by ice thickness, roughness, and fracture potential and develop assessment strategies with accuracy at the relevant spatial scales. In response to the widely reported importance of high-confidence ice thickness measurements, I have developed a new strategy to estimate appropriate thickness compensation factors. Compensation factors have the potential to reduce risk of misrepresenting areas of thin ice when using point-based in-situ assessment methods along a particular route. This approach was tested on an ice road near Kotzebue, Alaska, where substantial thickness variability results in the need to raise thickness thresholds by 50%. If sea ice is thick enough for safe travel, then the efficiency of travel is relevant and is influenced by the roughness of the ice surface. Here, I develop a technique to derive trafficability measures from ice roughness using polarimetric and interferometric synthetic aperture radar (SAR). Validated using Structure-from-Motion analysis of imagery obtained from an unmanned aerial system near Utqiaġvik, Alaska, I demonstrate the ability of these SAR techniques to map both topography and roughness with potential to guide trail construction efforts towards more trafficable ice. Even when the ice is sufficiently thick to ensure safe travel, potential for fracturing can be a serious hazard through the ability of cracks to compromise load-bearing capacity. Therefore, I have created a state-of-the-art technique using interferometric SAR to assess ice stability with capability of assessing internal ice stress and potential for failure. In an analysis of ice deformation and potential hazards for the Northstar Island ice road near Prudhoe Bay on Alaska's North Slope I have identified a zone of high relative fracture intensity potential that conformed with road inspections and hazard assessments by the operator. Through this work I have investigated the intersection between ice use and geophysics, demonstrating that quantitative evaluation of a given region in the ice use assessment framework developed here can aid in tactical routing of ice trails and roads as well as help inform long-term strategic decision-making regarding the future of Arctic operations on or near sea ice

Polarimetric Synthetic Aperture Radar, Principles and Application

Demonstrates the benefits of the usage of fully polarimetric synthetic aperture radar data in applications of Earth remote sensing, with educational and development purposes. Includes numerous up-to-date examples with real data from spaceborne platforms and possibility to use a software to support lecture practicals. Reviews theoretical principles in an intuitive way for each application topic. Covers in depth five application domains (forests, agriculture, cryosphere, urban, and oceans), with reference also to hazard monitorin

Remote sensing of sea ice properties and dynamics using SAR interferometry

Landfast ice is attached to the coastline and islands and stays immobile over most of the ice season. It is an important element of polar ecosystems and plays a vital role as a marine habitat and in life of local people and economy through offshore technology. Landfast ice is routinely used for on-ice traffic, tourism, and industry, and it protects coasts from storms in winter from erosion. However, landfast ice can break or experience deformation in order of centimeters to meters, which can be dangerous for the coastline and man-made structures, beacons, on-ice traffic, and represents a safety risk for working on the ice and local people. Therefore, landfast ice deformation and stability are important topics in coastal engineering and sea ice modeling. In the framework of this dissertation, InSAR (SAR Interferometry) technology has been applied for deriving landfast ice displacements (publication I), and mapping sea ice morphology, topography and its temporal change (publication III). Also, advantages of InSAR remote sensing in sea ice classification compared to backscatter intensity were demonstrated (publications II and IV). In publication I, for the first time, Sentinel-1 repeat-pass InSAR data acquired over the landfast ice areas were used to study the landfast ice displacements in the Gulf of Bothnia. An InSAR pair with a temporal baseline of 12 days acquired in February 2015 was used. In the study, the surface of landfast ice was stable enough to preserve coherence over the 12-day period, enabling analysis of the interferogram. The advantage of this long temporal baseline is in separating the landfast ice from drift ice and detecting long-term trends in deformation maps. The interferogram showed displacements of landfast ice on the order of 40 cm. The main factor seemed to be compression by drift ice, which was driven against the landfast ice boundary by strong winds from southwest. Landfast ice ridges can hinder ship navigation, but grounded ridges help to stabilize the ice cover. In publication III, ridge formation and displacements in the landfast ice near Utqiaġvik, Alaska were examined. The phase signatures of two single-pass bistatic X-band SAR (Synthetic Aperture Radar) image pairs acquired by TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurements) satellite on 13 and 24 January 2012 were analyzed. Altogether six cases were identified with ridge displacement in four and formation in two cases under onshore compression. The ridges moved approximately 0.6 and 3.7 km over the study area and ridge formation reached up to 1 meter in upward. The results well corresponded with the locations identified as convergence zones retrieved from the drift algorithm generated by a SAR-based sea ice-tracking algorithm, backscatter intensity images and coastal radar imagery. This method could potentially be used in future to evaluate sea ice stability and ridge formation. A bistatic InSAR pair acquired by the TanDEM-X mission in March 2012 over the Bothnian Bay was used in two further studies (publications II and IV). The potential of X-band InSAR imagery for automated sea ice classification was evaluated. The first results were presented in publication II and the data were further elaborated in publication IV. The backscatter intensity, coherence magnitude and InSAR-phase features, as well as their different combinations, were used as the informative features in classification experiments. In publication II, the purpose was to assess ice properties on the scale used in ice charting, with ice types based on ice concentration and sea ice morphology, while in publication IV, a detailed small-scale analysis was performed. In addition, the sampling design was different in these publications. In publication II, to achieve the best discrimination between open water and several sea-ice types, RF (Random Forests) and ML (Maximum likelihood) classifiers were employed. The best overall accuracies were achieved by combining backscatter intensity & InSAR-phase using RF approach and backscatter intensity & coherence-magnitude using ML approach. The results showed the advantage of adding InSAR features to backscatter intensity for sea ice classification. In the further study (publication IV), a set of state-of-the-art classification approaches including ML, RF and SVM (Support Vector Machine) classifiers were used to achieve the best discrimination between open water and several sea-ice types. Adding InSAR-phase and coherence magnitude to backscatter intensity improved the OA (Overall Accuracy) compared to using only backscatter intensity. The RF and SVM algorithms gave somewhat larger OA compared to ML at the expense of a somewhat longer processing time. Results of publications II and IV demonstrate InSAR features have potential to improve sea ice classification. InSAR could be used by operational ice services to improve mapping accuracy of automated sea ice charting with statistical and machine learning classification approaches.Viime vuosikymmeninä satelliittivälitteisestä SAR-tutkasta on tullut erittäin tärkeä työkalu merijään kaukokartoituksessa. Tämän tutka perustuu sähkömagneettisten aaltojen sirontaan kiinnostavasta kohteesta takaisin tutkaan, mitä seuraa signaalin voimakkuuden mittaaminen. SAR-tutkat käyttävät synteettistä antennia, joka perustuu satelliitin liikkeeseen, mikä mahdollistaa tarkkojen, korkean erotuskyvyn kuvien tuottamisen. SAR-anturit mittaavat myös signaalin vaihetta, jota käytetään interferometria tekniikassa pinnan topografian ja siirtymien laskemiseen eri sovelluksissa, kuten maan muodonmuutoksissa, tarkassa kartoituksessa, maanjäristyksen arvioinnissa ja tulivuorenpurkauksien tarkkailussa. Interferometri tekniikkaa käytettiin tässä opinnäytetyössä pienten jäänsiirtymien analysointiin kiintojäävyöhykkeellä, joka on kiinni rantaviivassa ja saarissa eikä juuri liiku tuulien tai virtausten mukana. Kiintojääalueilla on pohjaan tarttuneita jäävalleja, jotka edistävät kiintojääpeitteen vakautumista. Kiintojäällä on tärkeä rooli merellisenä elinympäristönä, maankäytön kysymyksissä sekä paikallisten ihmisten elämässä ja meritekniikassa. Kiintojää voi murtua liikahdella useita metrejä, mikä voi olla vaarallista rakenteille, majakoille ja jäällä liikkujille. Tässä väitöskirjassa Sentinel-1A ja TanDEM-X satelliitteja ja interferometri tekniikkaa on käytetty arktisilla alueilla ja Itämerellä mittaamaan kiintojään muodonmuutoksia ja siirtymiä sekä niihin liittyviä mekanismeja. Lisäksi on tutkittu automaattista merijääluokitusta interferometrian apuohjelmiston avulla, mikä laajentaa operatiivisten merijääpalvelujen tutkahavaintojen käyttöä. Sentinel-1A:n avulla voitiin tarkastella 12 päivän pituisia muutoksia Pohjanlahden kiintojäävyöhykkeellä, kun interferometria tekniikka mittasi voimakkaan tuulen aiheuttaman 40 cm:n siirtymiä. Pohjoisella jäämerellä voitiin tunnistaa jäävallien siirtymiä ja muodostumia. Vallit siirtyivät noin 0,6 ja 3,7 km matkoja ja muodostuessaan ne kasvoivat metrin korkeuteen. Interferometri tekniikan lisääminen tutkakuvauksen analyysiin osoitti potentiaalin parantaa automaattisen merijääkartoituksen kartoituksen tarkkuutta tilastollisilla ja koneoppimiseen perustuvan luokittelun menetelmillä. Tulevaisuuden työnä merijään luokituksessa ja vallitutkimuksissa olisi suositeltavaa käyttää erilaisia ja useampia tutkakuvauksen geometrioita sekä erilaisia jääolosuhteita eri sääolosuhteiden vallitessa

Multi-sensor techniques for the measurement of post eruptive volcanic deformation and depositional features

Thesis (Ph.D.) University of Alaska Fairbanks, 2019Remote sensing of volcanic activity is an increasingly important tool for scientific investigation, hazard mitigation, and geophysical analysis. These studies were conducted to determine how combining remote sensing data in a multi-sensor analysis can improve our understanding of volcanic activity, depositional behavior, and the evolutionary history of past eruptive episodes. In a series of three studies, (1) optical photogrammetry and synthetic aperture radar are combined to determine volumes of lahars and lava dome growth at Redoubt Volcano, Alaska; (2) applied data from multiple synthetic aperture radar platforms are combined to model long-term deposition of pyroclastic flow deposits, including past deposits underlying current, observable pyroclastic flow deposits at Augustine Volcano, Alaska; and finally (3) combined, low-spatial-resolution thermal data from Advanced Very High Resolution Radiometer sensors are combined with high resolution digital elevation models derived from the microwave TanDEM-X mission, to increase the accuracy of eruption profiles and effusion rates at Tolbachik Volcano on the Kamchatka Peninsula, Russian Far East. As a result of this study, the very diverse capabilities of multiple remote sensing instruments were combined to improve the understanding of volcanic processes at three separate locations with recent eruptive activity, and to develop new methods of measurement and estimation by merging the capabilities of optical, thermal, and microwave observations. With the multi-sensor frameworks developed in this study now in place, future efforts should focus on increasing the diversity of sensor types in joint analyses, with the objective of obtaining better solutions to geophysical questions

Annual report 2007 - North Pacific Marine Science Organization (PICES). Sixteenth meeting, Victoria, Canada, October 26-November 5, 2007

Report of Opening Session (p. 1). Report of Governing Council (p. 15). Report of the Finance and Administration Committee (p. 65). Reports of Science Board and Committees: Science Board Inter-Sessional Meeting (p. 83); Science Board (p. 93); Biological Oceanography Committee (p. 105); Fishery Science Committee (p. 117); Marine Environmental Quality Committee (p. 129); Physical Oceanography and Climate Committee (p. 139); Technical Committee on Data Exchange (p. 145); Technical Committee on Monitoring (p. 153). Reports of Sections, Working and Study Groups: Section on Carbon and Climate (p. 161); Section on Ecology of Harmful Algal Blooms in the North Pacific (p. 167); Working Group 19 on Ecosystem-based Management Science and its Application to the North Pacific (p. 173); Working Group 20 on Evaluations of Climate Change Projections (p. 179); Working Group 21 on Non-indigenous Aquatic Species (p. 183); Study Group to Develop a Strategy for GOOS (p. 193); Study Group on Ecosystem Status Reporting (p. 203); Study Group on Marine Aquaculture and Ranching in the PICES Region (p. 213); Study Group on Scientific Cooperation between PICES and Non-member Countries (p. 225). Reports of the Climate Change and Carrying Capacity Program: Implementation Panel on the CCCC Program (p. 229); CFAME Task Team (p. 235); MODEL Task Team (p. 241). Reports of Advisory Panels: Advisory Panel for a CREAMS/PICES Program in East Asian Marginal Seas (p. 249); Advisory Panel on Continuous Plankton Recorder Survey in the North Pacific (p. 253); Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (p. 255); Advisory Panel on Marine Birds and Mammals (p. 261); Advisory Panel on Micronekton Sampling Inter-calibration Experiment (p. 265). 2007 Review of PICES Publication Program (p. 269). Guidelines for PICES Temporary Expert Groups (p. 297). Summary of Scientific Sessions and Workshops (p. 313). Report of the ICES/PICES Conference for Early Career Scientists (p. 355). Membership (p. 367). Participants (p. 387). PICES Acronyms (p. 413). Acronyms (p. 415)

Overwinter sea-ice characteristics important for Antarctic krill recruitment in the southwest Atlantic

Climate change alters the extent and structure of sea-ice environments, which affects how they function as a habitat for polar species. Identifying sea-ice characteristics that serve as indicators of habitat quality will be crucial to the monitoring and management of climate change impacts. In the Southern Ocean, Antarctic krill is a key prey species and fishery target. Krill larvae depend upon sea-ice habitats to survive the winter and recruit to the population in spring. Existing observations of sea-ice characteristics lack sufficient spatiotemporal coverage to quantify which ones contribute to favourable overwintering habitat, leading to uncertainties in how current and future changes in sea ice affect krill populations. Here, we derive regional-scale indices of annual krill recruitment spanning 35 years across the southwest Atlantic. To develop meaningful indicators of sea-ice habitat, we selected variables from a high-resolution sea-ice model that are hypothesized as relevant for larval habitat use. The resulting correlations between recruitment and sea-ice indicators vary by region and show remote connections to sea ice that correspond with established theories of larval transport. Through an improved representation of sea-ice habitat quality, as compared with using more traditional satellite-derived variables such as sea-ice extent and duration, we highlight plausible regions of overwintering habitat. Our findings improve current understanding of how krill are likely responding to changing sea ice and support emerging views that larval habitat use is complex. Furthermore, regional variation in larval dependence on sea ice may provide pockets of resilience to change for the broader krill population