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GEORGE MASON UNIVERSITY (2004)

Regional monitoring of environmental physics climate related anomalies

El-Askary, Hesham

Titre  : Regional monitoring of environmental physics climate related anomalies

Auteur  : El-Askary, Hesham

Université de soutenance : GEORGE MASON UNIVERSITY

Grade : Doctor of Philosophy (PhD) 2004

Mots clés : PHYSICS, ATMOSPHERIC SCIENCE ; REMOTE SENSING

Résumé
Scientific communities have been working in creating and enhancing scientific research programs in which in situ and satellite data as well as remote sensing (RS) technologies are being applied to regional environmental issues. These issues include the effects of climate change on regional flooding, droughts and the impact of human activities as they relate to feedbacks on the global climate. More specifically, one needs to evaluate the potential impact of climatological variability on social, economic, and human activities. In addition, the study of their effects on agriculture, forests, local natural ecosystems and water climate-related resources, is most important. Finally, dust storms and other natural events such as droughts can have great local impacts. Approximately half of the dust in today’s atmosphere may be the result of changes to the environment caused by human activities, including agriculture, overgrazing, anddeforestation. Climate variability may lead to the occurrence of some severe environmental phenomena like dust storms, hurricanes, tomadoes, floods and droughts. Under normal conditions we can detect different dust effects associated with the movement of storms as well as different rain pattems that do not affect much of the surrounding environment either at regional or global scales. On the other hand, under abnormal climatological conditions, high anomalies of precipitation might occur due to the presence of hurricanes or other events, leading to severe flooding events. In this dissertation, we apply time series analysis techniques to remote sensing and in situ data to detect precipitation and dust storm anomalies and study their behavior on regional scales. The first application is the detection and monitoring of dust storms events over parts of the Middle East and Asia. Dust storms cause health and economic hazards. In this thesis dust storms development is examined based on using remote sensing technology. It utilizes a combination of optical sensing using the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Terra, with microwave sensing using the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI). This approach has the potential to be superior to currently used methods by distinguishing aerosol particles from dust particles based on their grain sizes. The Middle East, particularly Egypt and the Gulf region, is selected for such application since it is located on the northem part of the desert belt, and hence is considered to be an excellent loeation for dust measurements. Egypt is subject to industrial pollution and therefore the complex interactions of dust with industrial aerosols can affect precipitation and Earth’s radiationbudget. Another location, Indo-Gangetic basin, India is also selected since it experiences heavy dust storms that originate from the Saharan desert during the pre-monsoon period. In the application over India, the Multi-angle Imaging SpeetroRadiometer (MISR) technology was used. The second application in this dissertation is the study of precipitation variability over the Mid-Atlantic region to help understanding the behavior causing anomalies like flooding and drought events. The impacts of global climate phenomena such as El Nino and La-Nina are studied emphasizing how strongly they affect or cause these events on regional scales.

Présentation : ProQuest Digital Dissertations

Page publiée le 16 septembre 2004, mise à jour le 14 janvier 2017