Improving Regional Climate Modeling in East Africa Using Remote Sensing Products - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Improving Regional Climate Modeling in East Africa Using Remote Sensing Products write by Jianjun Ge. This book was released on 2007. Improving Regional Climate Modeling in East Africa Using Remote Sensing Products available in PDF, EPUB and Kindle.
Remote Sensing and Climate Modeling: Synergies and Limitations
Remote Sensing and Climate Modeling: Synergies and Limitations - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Remote Sensing and Climate Modeling: Synergies and Limitations write by Martin Beniston. This book was released on 2006-04-11. Remote Sensing and Climate Modeling: Synergies and Limitations available in PDF, EPUB and Kindle. 1 2 Michel M. VERSTRAETE and Martin BENISTON 1 Space Applications Institute, EC Joint Research Centre, Ispra, Italy 2 Department of Geography, University of Fribourg, Switzerland This volume contains the proceedings ofthe workshop entitled “Satellite Remote Sensing and Climate Simulations: Synergies and Limitations” that took place in Les Diablerets, Switzerland, September 20–24, 1999. This international scientific conference aimed at addressing the current and pot- tial role of satellite remote sensing in climate modeling, with a particular focus on land surface processes and atmospheric aerosol characterization. Global and regional circulation models incorporate our knowledge ofthe dynamics ofthe Earth's atmosphere. They are used to predict the evolution of the weather and climate. Mathematically, this system is represented by a set ofpartial differential equations whose solution requires initial and bo- dary conditions. Limitations in the accuracy and geographical distribution of these constraints, and intrinsic mathematical sensitivity to these conditions do not allow the identification of a unique solution (prediction). Additional observations on the climate system are thus used to constrain the forecasts of the mathematical model to remain close to the observed state ofthe system.
Land-atmosphere Interactions and Regional Climate in West Africa and South America
Land-atmosphere Interactions and Regional Climate in West Africa and South America - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Land-atmosphere Interactions and Regional Climate in West Africa and South America write by Amir Erfanian Javadian Entezar Yazd. This book was released on 2017. Land-atmosphere Interactions and Regional Climate in West Africa and South America available in PDF, EPUB and Kindle. Land, atmosphere, and oceans interact with each other through energy, mass, and momentum exchanges. These interactions regulate climate variability and influence climate changes at the regional scale. One notable example of highly influential land-atmosphere-ocean interactions on regional climates is monsoonal systems that influence a substantial portion of the world’s population. In this dissertation, the present and future climates of West Africa (WA) and South America (SA), two important monsoon regions, were studied utilizing Regional and Global Climate Models (RCMs and GCMs), mathematical techniques and data mining tools, and observational data (in-situ, remote-sensing, and reanalysis). The objective is to advance our understanding on the role of land-atmosphere-ocean feedbacks, especially vegetation-climate interactions, in the climate variability, change, and extremes over these regions. Special attention was given to the improvement of climate simulations and reliability of future climate projections by quantifying and/or reducing uncertainties from multiple sources. As part of this dissertation, two new approaches concerning regional climate modeling and projection were developed, each pertaining to one of the geographic domains. One is the Ensemble-based Reconstructed Forcings (ERF) method that faithfully reproduces the Multi-Model Ensemble (MME) mean but requires only a fraction of the computational cost of the conventional MME approach, which is critical for reducing the high uncertainties in the outlook of future precipitation change over WA. The other newly developed approach tackle the nesting practice, a major source of RCM bias that causes (large-scale) circulation in SA to drift away from that of the driving GCMs. To this end, a new paradigm of regional climate modeling was proposed that includes the influential oceans within the RCM domain to better resolve the large-scale circulation of the SA climate. Results from a fully coupled regional climate model, with and without dynamic vegetation, revealed significant influence of vegetation-climate interactions on the mean and variability of the surface hydroclimate of the two regions of focus. Precipitation, surface temperature, evapotranspiration, and soil moisture were all strongly influenced. In particular, results from both numerical experiments and observational data analysis indicated that tropical oceanic variability plays a dominant role in precipitation variability over SA, including the unprecedented extreme drought of 2016; in addition, greenhouse gas warming was found to significantly contribute to the amplification of the 2016 drought, especially during the pre-monsoon season. Natural vegetation dynamics improves the model performance in capturing the anomalies of surface water storage but has a negligible impact on precipitation anomalies of this extreme drought. Results of this research help advance our understanding and improve our capability to quantify and predict climate variability, change, and extremes over WA and SA.
Prediction and Numerical Simulation of the Regional Climate of Equatorial Eastern Africa
Prediction and Numerical Simulation of the Regional Climate of Equatorial Eastern Africa - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Prediction and Numerical Simulation of the Regional Climate of Equatorial Eastern Africa write by . This book was released on 2000. Prediction and Numerical Simulation of the Regional Climate of Equatorial Eastern Africa available in PDF, EPUB and Kindle. The objective in this investigation was to provide a better understanding of the mechanisms and physical processes responsible for climate variability over the equatorial eastern Africa, and explore potential for short-term climate prediction. Both statistical and numerical methods have been employed in this research. Application of cluster analysis yields 8 and 9 homogeneous climatic zones respectively for the variability of the annual and seasonal rainfall. Regions that are prone to drought or floods during the different phases of El Niño-Southern Oscillation (ENSO) are delineated. Positive rainfall anomalies occur in much of the region during March-May (MAM) and October-December (OND) of the ENSO(0) years and negative anomalies dominate during the following ENSO(+1) years. These rainfall patterns are useful for short-term climate monitoring over the region. The relationship between the Quasi-Biennial Oscillation (QBO) in the lower stratospheric zonal winds and the long-rains of MAM is more significant in lagged than in simultaneous, with the most distinct relationships occurring over the western parts of the region. The QBO-index explains about 36% of the seasonal rainfall variance. There is a 60/63 percent likelihood for the occurrence of above/below normal rainfall during the westerly/easterly phase of the QBO-index. The NCAR Regional Climate Model (RegCM2) simulations have demonstrated the added value of the nesting approach in improving regional climate simulations. The model reproduces the observed characteristics of the Turkana low-level jet. The study has shown the importance of orographic forcing, the large-scale background monsoon flow and depth of the channel in the development and maintenance of the jet. Thermal and frictional forcing play equivalent roles as that of the large-scale winds in the formation of the jet. The identified regions of strong winds associated with the jet are important to the safety in the aviation industry and are also pot.
Review of the available remote sensing tools, products, methodologies and data to improve crop production forecasts
Review of the available remote sensing tools, products, methodologies and data to improve crop production forecasts - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Review of the available remote sensing tools, products, methodologies and data to improve crop production forecasts write by Food and Agriculture Organization of the United Nations. This book was released on 2018-05-31. Review of the available remote sensing tools, products, methodologies and data to improve crop production forecasts available in PDF, EPUB and Kindle. Timely and reliable agricultural production forecasts are critical to make informed food policy decisions and enable rapid responses to emerging food shortfalls. Sub-Saharan Africa is subject to highly variable yield, production and consumption, occasioned by high climate variability, rapidly increasing populations, and limited financial capacity. This review examines the current status of the remote sensing (RS) tools, products, methodologies and data that can help to improve agricultural crop production forecasting systems.
