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Format: Digital (Available online for logged-in users)Based on Global Precipitation Climatology center (GPCC) precipitation data and Era-Interim Zonal and Meridional wind, relative humidity, Sea Level Pressure and Sea surface temperature data from ECMWF, Statistical methods were conducted to find out the interannual variability of rainfall and its dynamic factors in AGLR from 1981 to 2016. The results show that there are two (long and short) rainfall seasons over AGLR, MAM and OND respectively. The empirical orthogonal function was used to reveal through the dominant principal components (PC1) of the first EOF, the extreme years (wet and dry) for ...Published by: College of Atmospheric Science ; 2019
Spatial/Temporal Distribution of Rainfall and the Dynamic Factors Associated over African Great Lakes Region from 1981 to 2016
Based on Global Precipitation Climatology center (GPCC) precipitation data and Era-Interim Zonal and Meridional wind, relative humidity, Sea Level Pressure and Sea surface temperature data from ECMWF, Statistical methods were conducted to find out the interannual variability of rainfall and its dynamic factors in AGLR from 1981 to 2016. The results show that there are two (long and short) rainfall seasons over AGLR, MAM and OND respectively. The empirical orthogonal function was used to reveal through the dominant principal components (PC1) of the first EOF, the extreme years (wet and dry) for both MAM and OND. Since previous analysis have shown that OND rainfall has high variability than the long rainy season MAM, further analysis (composite analysis) was conducted to investigate the dynamic factors behind the extreme (wet and dry) years for OND season. Results of composite analysis suggest that the Indian Ocean SST regulates the precipitation over the study area; warm SST influences the wind circulation resulting in an upward motion of warm air due to convergence of wind during wet years and the contrary is observed during dry years.
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Format: Digital (Available online for logged-in users)The surface wave investigation and monitoring (SWIM) will be one of the two payload instruments carried by China France Oceanography Satellite (CFOSAT) with a planned launch date in mid-2018. SWIM has six beams rotating around the vertical axis at incidence angles 0,2,4,6,8,10 degree. With nadir-beam, the SWH and wind speed can be detected as the same principle as an altimeter. At the same time, the ocean wave spectrum beams can also Catch the significant wave height (SWH). To find which SWH is more stable and accurate, first, the thesis presents an overview of SWH detection from a satellite. ...Published by: School of Marine Science, NUIST, ; 2018
The surface wave investigation and monitoring (SWIM) will be one of the two payload instruments carried by China France Oceanography Satellite (CFOSAT) with a planned launch date in mid-2018. SWIM has six beams rotating around the vertical axis at incidence angles 0,2,4,6,8,10 degree. With nadir-beam, the SWH and wind speed can be detected as the same principle as an altimeter. At the same time, the ocean wave spectrum beams can also Catch the significant wave height (SWH). To find which SWH is more stable and accurate, first, the thesis presents an overview of SWH detection from a satellite. Then the principles of SWH detected from the altimeter, and the spectra beams of SWIM are reviewed. Finally, the comparison of SWH from ocean wave spectra beam and nadir beam of SWIM is performed according to the simulated data. The results show that the SWH from nadir beam is more accurate and stable than from spectra beam.
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Format: Digital (Free)Agriculture is the largest employer in the world and is probably the most dependent on the climate of all human activities. In recent years there have been events that have put in evidence the vulnerability of global food security to major meteorological phenomena, both in global agricultural markets and the world economy. The food price crisis and the subsequent economic crisis reduced the purchasing power of large segments of the population in many developing countries, which seriously reduced their access to food and thus undermined their food security. During the years 2009 and 2010 in Ven ...Published by: Министерство Образования и Науки Российской Федерации ; 2018
Agriculture is the largest employer in the world and is probably the most dependent on the climate of all human activities. In recent years there have been events that have put in evidence the vulnerability of global food security to major meteorological phenomena, both in global agricultural markets and the world economy. The food price crisis and the subsequent economic crisis reduced the purchasing power of large segments of the population in many developing countries, which seriously reduced their access to food and thus undermined their food security. During the years 2009 and 2010 in Venezuela there were strong weather anomalies, drought in the first case and the second extreme rains, caused mainly by the effect of the El Niño-Southern Oscillation (ENSO) event, with warm phase (El Niño) in 2009 and cold phase (La Niña) in 2010, affecting farming, mostly in Monagas, Anzoátegui and Guárico States negatively influencing its economy. The planning of agricultural production based on the use of agricultural information, as calendars of sowing, as well as the monitoring of the conditions during the crop cycle and the use of agrometeorological forecasting, then is of great importance for the development of the agricultural sector, because it minimizes the effects on food production which might be affected by climate variability, making it less vulnerable. Model results confirm the importance of known key physiological processes, such as the shortening of the time to maturity of a crop with increasing mean temperature, decline in grain set when high temperatures occur during flowering, and increased water stress at high temperatures throughout the growing cycle. Temperature responses are generally well understood for temperatures up to the optimum temperature for crop development. The impacts of prolonged periods of temperatures beyond the optimum for development are not as well understood. For this study the agro meteorological stations selected have daily records of all climatic elements, so it held a summary monthly apart from daily data (with prior quality control) for the accumulated monthly rainfall and temperature maximum and minimum for the 1971-2010 series. Therefore, Inter decadal rainfall and temperature analysis and the use of the cropwat 8.0 to model future scenarios can be estimated water requirements of main crops, allowing some adaptation measures to help mitigate the effects of climate change in the country's agricultural production. In selected stations were determined significant changes on ETc when the temperature increase and the availability of water is a key factor to reach the harvest. Adaptation measurements involve reducing risk and vulnerability; for developing countries rely heavily on climate-dependent agriculture and especially in conjunction with poverty and rapid increase in population they are vulnerable to climate change.
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Format: Digital (Free)The conference provides an opportunity for students especially PhD students to present their work and get feedback from other professionals. Not only that but the it also offers an excellent chance for networking among aspiring scientists and the possibility for future collaborations.Published by: University of Reading ; 2017
Evaluation of subseasonal prediction of extreme rainfall events and their relationship with the Madden Julian Oscillation over the Solomon Islands
The conference provides an opportunity for students especially PhD students to present their work and get feedback from other professionals. Not only that but the it also offers an excellent chance for networking among aspiring scientists and the possibility for future collaborations.
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Format: Digital (Free)PermalinkPermalinkRainfall is a very important weather and climate parameter that affects social and economic activities in Djibouti. This leads to droughts, floods and humanitarian disasters over the country. The rainfall climatology of the country has some changes which need to be taken into account while planning for economic activities such as civil and structural engineering. The whole country receives significant rains in the months of (October – December) and (March – April) as known except for the southern parts of the country. The southern part of the country gets its rains in the months of (June to Au ...PermalinkFloods and droughts are one of extreme weather climatic events that result in loss of life and property in Malawi. However, a well detailed knowledge of understanding of previous extreme climatic events and their associated impacts can be a precautionary in reducing their impacts, as it will help to project future events timely. Therefore this paper presents an analysis of Dec-Feb seasonal flood/drought events and their associated circulation anomalies over Malawi. The DJF seasonal flood/drought was studied using monthly data from 9 selected stations for the period of 1978-2010. A set of regio ...PermalinkAs we know tropical intraseasonal oscillation (ISO) was described as 2 modes such as Boreal summer intraseasonal oscillation (BSISO) during boreal summer and Madden-Julian Oscillation (MJO) dominates during boreal winter. In summer time, Thailand where located at the coastal region at the Equator which is effected by BSISO. Some week there is strong diurnal cycle but some week is opposite. The purpose of this work is to study the evolution of BSISO and to study the change of diurnal precipitation in different phases of BSISO. Tropical Rainfall Measuring Mission (TRMM) version 3B42 data on 0.25 ...PermalinkAgriculture is the largest employer in the world and is probably the most dependent on the climate of all human activities. In recent years there have been events that have put in evidence the vulnerability of global food security to major meteorological phenomena, both in global agricultural markets and the world economy. The food price crisis and the subsequent economic crisis reduced the purchasing power of large segments of the population in many developing countries, which seriously reduced their access to food and thus undermined their food security. During the years 2009 and 2010 in Ven ...PermalinkClimate is one of the key factors that affect agriculture. Climate change and climate variability have been observed, typically shown as global warming due to the increased greenhouse gases. The change in climate is even predicted to be rapped and sharp in recent future and the impacts of extreme climate condition associated with climate change will be high on agriculture. Studying the impacts of climate change, especially the effects of temperature and precipitation on agriculture, is important for food safety, agricultural management, and sustainable development.PermalinkDans ce travail nous avons voulu étudier sur la zone tropicale les liens entre les systèmes convectifs et la pluie. L’algorithme TOOCAN introduit a pour but d’améliorer la caractérisation de l’évolution du bouclier nuageux associe aux systèmes convectifs au cours de leur cycle de vie. Des composites des structures précipitantes au cours du cycle de vie du système nuageux organise sont alors construits en fusionnant les données des satellites géostationnaires avec des estimations de précipitations issues des mesures micro-ondes à bord des satellites défilant. L’objectif de ce travail est non se ...PermalinkThis study investigates spatial and temporal features of the West African Summer Monsoon (WASM) and its relation to the Sea Surface Temperature Anomaly (SSTA). The variability of the WASM from June to September was analyzed during the period 1960-2013, with methods including EOF analysis of the precipitation anomaly and SSTA and the associated large scale circulation pattern. The result from the first EOF-Mode of the precipitation anomaly which has the highest positive loadings over the region shows that during the summer, the precipitation anomalies are positives in the Sahel and the Sahara. ...PermalinkPermalinkTo apprehend the temporal and spatial distribution of the rainfall over CAR, we computed thirty-three years (1981-2013) of monthly rainfall, relative humidity over the country divided into four (4) distinct sub-regions. Bearing different characteristics one to another, we found that Region 2 and Region 4 were having a statistical significant upward trend along the long term rainfall variation; meanwhile Region 3 was the one having a highest coefficient of variation on the yearly basis. The composite analysis showed that December, January and February were the months with higher frequency of va ...PermalinkThe rainy season in Sierra Leone is unimodal from April to October; an understanding of the inter-annual variability of rainfall in Sierra Leone is of importance to economic sectors such as fisheries, agriculture, infrastructure, hydro-electric power generation (HEP) and water resources. This study investigated the variation of the intra-seasonal rainfall characteristics in Sierra Leone. Daily rainfall data from 4 synoptic stations was obtained from the Sierra Leone Meteorological Department from 1990-2014.PermalinkFog though a rare event has adverse economic implications to both the airline and aviation service providers if it’s occurrence, duration and dissipation periods are not properly predicted. This work assesses the accuracy and skill in forecasting fog events and suggesting possible adjustments to improve forecast accuracy and skill. The forecast used in this study are produced by MeteoGroup using Model Output Statistics (MOS). Forecasts for Heathrow, Northolt and Kenley are considered for analysis. These forecasts are used by British Airports Authority (BAA) in planning airport operations. The ...PermalinkWhile drought conditions are generally a common and recurring phenomenon of the climate in Southern Africa especially Lesotho, the frequency of droughts in Lesotho has increased significantly over the past few years. Lesotho has suffered the devastating impacts of drought during the past several decades resulting in poor harvests and large livestock losses to rural farmers. The majority of the population in Lesotho engages with rain- fed agriculture and is dependent to some degree on own production for household food supply and/or cash income (Dejene, Midgley, & Marake, 2011). Any negative cha ...PermalinkThis study attempted to investigate the variability of extreme rainfall and temperature over Rwanda and the associated circulation anomalies forecasting on wet and dry rainfall events between 1961 and 2010. The datasets used to achieve the objectives includes Temperature, the rainfall dataset, wind vector, pressure vertical velocity (omega) and the Indian Ocean sea surface temperature (SST). The methods used include correlation analysis, Standardized anomaly, composite analysis, and Empirical Orthogonal Functions (EOF) analysis. The results show that the mean annual cycle depict two rainy Seas ...PermalinkThe Sahel drought mechanism: insights from two contrasting extreme events during boreal summer July-August-September (JAS) is investigated in this study using the standardized precipitation index (SPI). Empirical orthogonal function (EOF) and composite analyses were deployed in this study, where the global precipitation climatology center (GPCC) rainfall data is used. The SPI shows large widespread decreasing rainfall trend in the Sahel in the mid-1980s; thereafter, Sahel rainfall have recovered somewhat through the late 1990s, even though the drought conditions have not ended in the region. A ...PermalinkGlobal climate change is remarkably changing the climatic patterns of the Pearl River basin and are significantly impacting the hydrological processes. Projection of future climate change impacts on steamflow variation is potential to provide scientific guidelines for sustainable water resources management and effective prevention and control for flood and drought disasters. In this study, a hydrological modeling system for assessing climate change impacts on runoffin the Pearl River basin was established and were used to simulate historical hydrological process and to project future streamflo ...PermalinkThis research investigates the dynamical and thermodynamical process of mesoscale convective system that intensifies squall lines wind speed propagation. The generation of African Easterly Waves (AEWs) and its lifecycle. The characteristics of squall lines (SLs) over West Africa (WA) which occurred In Guinea for two cases periods June 01-02 and June 13-14, 2015. In all six (6) AEWs have been tracked using reanalysis data from European Centre for Medium-Range Weather Forecasts (ECMWF). European Meteorological Satellite images (EUMETSAT) and Earth Networks WeatherBug StreamerRT were also used to ...PermalinkAerosols are small, micrometer-sized particles, whose optical effects coupled with their impact on cloud properties is a source of large uncertainty in climate models. Aerosols when inhaled are believed to have significant and detrimental effects on human health. Their presence also affects photosynthesis and agricultural production. Aerosol measurements are urgently required for the complete understanding and modeling their role in the climate system. This study builds on the analysis of Aerosol Optical depth (AOD) using Light Detection and Ranging (LIDAR) and sun photometer measurements then ...PermalinkThis paper examines the aerosol extinction coefficient profiles measured by Rayleigh-Raman-Mie-Lidar (RRML) system in Nanjing, China. I introduced two lidars methods (Raman and Fernald) and detection principle, and two lidars data Using Raman analysis method and Fernald analysis method to obtained aerosol extinction coefficient. Aerosol profiles at 607 nm and 532 nm over ranges from 6 km to 10 km were obtained using respectively Raman lidar and Rayleigh lidar in Nanjing.PermalinkPrecipitations vary consistently in Benin from 1981 to 2010. The present study reveals that the variation of Benin JJAS precipitation is positively correlated to MAM Sea Surface Temperature (SST) in Atlantic Ocean with correlation coefficient more than 0.7. When the SST is higher (lower) in the Atlantic Ocean, precipitation over Benin tends to be above (below) normal. The years 1988, 1989, 2003, 2007 and 2008, were wet with 1988, 2003, 2008 high SST over Tropical Southern Atlantic Ocean (STAO) while the years 1982, 1983, 1992 and 1997 formed the dry years with low SST over Tropical Southern At ...PermalinkThe southern coastal region of West Africa (SCWA) is located between 40N-80N latitudes and 100W -50E longitudes near the equator in the northern Hemisphere, the south and west are respectively equatorial and West Atlantic Ocean, and it is consisted to seven countries (Sierra Leon, Liberia, Cote d’Ivoire, Ghana, Togo, Benin and Nigeria). The rainy season starts from spring to the summer, mainly from May to October. The rainfall is very important for southern coastal of West Africa region which their economy and food supply are highly dependent on agricultural production. Understanding of previo ...PermalinkThe variability and predictability of summer rainfall over Zimbabwe at inter-annual time scale is studied. Dry and wet seasons are identified using Zimbabwe Standardized Rainfall Index (ZRI). Seasonal rainfall and circulation patterns are investigated at inter annual time scale. The study focuses on the temporal and spatial variation of summer rainfall over Zimbabwe and tries to explain the circulation mechanisms associated with such phenomenon.PermalinkThe current study is an attempt to assess meteorological drought in Myanmar during the South west pre monsoon and monsoon period using observed rainfall data from 34 stations in Myanmar spanning from 1971 to 2010. The components of drought that were analyzed in this study were severity, persistence, frequency and probability of occurrence. Additional, trends in drought occurrence were analyzed using the Mann-Kendall (MK) method while the wavelet analysis was applied to PI value to identify various periodic processes.PermalinkFor Zimbabwe, where rain fed agriculture is the backbone of the economy, the importance of accurate rainfall seasonal forecasts cannot be overemphasized (Makarau and Jury, 1997). In fact, extremes in interseasonal variability of rainfall can significantly complicate human livelihoods. In addition, there have been predictions of increased precipitation variability and hydro-meteorological hazards such as floods, droughts, and erratic rainfall due to global warming (Field et al., 2014; Mushore, 2013a). Thus, detailed understanding of the major contributors to the rainfall variability over Zimbab ...PermalinkDroughts pose a major risk in most African countries including Ghana where agricultural activities are heavily dependent on rainfall. Efforts at assessing droughts and providing decision support tools to farmers are hampered by a lack of rainfall and other meteorological data over many parts of Africa. Satellite based rainfall measurements have been suggested to fill the rainfall data gaps over Africa to enable effective assessment of droughts. Traditional methods of assessing droughts have been based on statistical formulations that relied mostly on precipitation. This approach to assessing d ...PermalinkIn urban climate research, spatial and temporal variability of precipitation is always a critical element for numerical modelling. However, the effects of temporal resolution of precipitation forcing data has received little attention. Moreover, there has always been a difference practically and theoretically in the availability of precipitation data. This study was carried out to assess the impact of temporal resolution of precipitation forcing data on the modelled surface energy and water balance using available data from a site at the Strand campus of Kings College London. Analysis has been ...PermalinkForecasting heavy rainfall associated with in-situ convective cloud development over small island states is a challenge in operational forecasting as not all numerical models are able to resolve convection at such small scales. Forecasting of such phenomena is mainly based on prevailing local conditions and the use of a plethora of thermodynamic indices derived from the local sounding. This study is an effort to assess the suitability of the different available indices, hereafter referred as traditional indices, to forecast heavy rainfall from local convection, commonly known as pure sea breez ...PermalinkAerosols in the atmosphere serve as condensation nuclei for the cloud formation. This brings an important influence on the microphysical properties of cloud water that in turn affect the processes in the formation of precipitation. Aerosol-cloud-precipitation interaction which simultaneously change cloud albedo interest many studies to find out aerosol impact on precipitation formation. The studies were done by observation measurement and simulation. UK Met Office Unified Model (UM) is one model that includes aerosol direct and indirect effect in the NWP configuration which leads to study aero ...PermalinkThis study attempts to reveal features of rainfall over Togo, in relationship to the
prevailing atmospheric circulation. The study employed correlation analysis and composite analysis in
the analysis of rainfall, sea surface temperature, wind, and humidity. Empirical orthogonal functions
(EOF) analysis was employed in this study. The years: 1989, 1991, 1995, 2003 and 2007 were
identified to be anomalously wet years while 1982, 1983, 1990, 1992, 2001 and 2006 fall in the
anomalously dry years’ category. The dominant mode of variability exhibits a dipole patter ...PermalinkAbongnwi Ngwa Lumfuh - 2014Adverse weather is the main cause of the alterations to operations at Wilson airport. At Wilson airport, occurrence of fog and low ceiling, cross winds, thunderstorm and heavy rainfall are considered the main causes of adverse weather hampering the aircraft operations. The purpose of this study is to investigate the impacts of fog and thunderstorm on aircraft operations at Wilson airport. The impact is measured in terms of delay, diversion, cancelation and economic value of these actions. The data on fog and thunderstorm data was obtained from Kenya Meteorological Service (Climatological secti ...PermalinkThe attachment took place at the ECMWF headquarters in Reading, United Kingdom from 29th April-30th July 2013. The program was sponsored by the World Meteorological Organisation (WMO).PermalinkMafuru Kantamla Biseke - College of Atmospheric Science, Nanjing University of Information Science and Technology, 2013Tanzania is one among the most other sub-Sahara African countries where Agriculture production is strongly depending on rainfall, a key factor which determine the livelihood of 70% of the total population. An adequate amount of rainfall per season reasonably help the farmer to accomplish his/her goal in a positive way, while an excessive amount of rainfall impacts on both people’s livelihood and agricultural production leading into reduction in manpower and nation’s GDP. In recent years, Tanzania suffered a successive scenario of heavy rainfall over different areas of the country, the majority ...PermalinkTemperature and rainfall are important elements of climate Zambia where several sectors of the economy depend mostly on water resources. Zambia normally receives the bulk of its annual rainfall from November to March (NDJFM) as the ITCZ moves south and experience high temperatures. The major objective of the study was to investigate the rainfall and temperature characteristic over Zambia.PermalinkFloods are a threat to many cities especially in the developing countries and cities found near the coastal areas where the population pressure, unplanned settlements and poor infrastructures are most evident. Climate change also poses a higher flood risks in these areas due to increased frequency and intensity of extreme rainfall events. In this study analysis of extreme rainfall over Dar es Salaam city in Tanzania was done. The analysis employed empirical as well as hydrological frequency modeling to annual maximum daily rainfall events for 5 of the meteorological stations found within the c ...PermalinkMany studies carried out have shown evidence of regional temperature and precipitation variability along with global climate changes. A key issue is whether these variability follow trends that are uniform or others have increasing trends while others decreasing trend. And this study was carried out using Mann-Kendall trend test method and regression analysis method with the data observed by a total of 20stations to investigate the trends of temperature and precipitation in northern China. 10stations were selected from urban areas (section 1.4.2: table 1.1) and another 10stations were selected ...PermalinkApart from the northern coast, most of Egypt is desert. However, the northern coastal region experiences some precipitation mainly during winter. We investigate the variability of wintertime (December, January and February) precipitation in North Egypt during the 30-yr interval 1976-2005 and its relationship with the North Atlantic Oscillation during winter and subtropical jet stream.PermalinkUganda is located between latitudes 1.5 0 S to 4.5 0 N and longitudes 28o E to 35 0 E. It contains complex topography that includes large Lakes, Rivers, Great Rift Valley and Mountains, and supports varied wildlife of scientific and economic value. Due to its Equatorial location, this country is expected to receive abundant rainfall throughout the year. This is, however, not the case as frequent occurrences of years of insufficient rainfall for agricultural activities have been observed. Rainfall over Uganda exhibits large spatial and temporal variability. The inter-annual variability has feat ...Permalink“The dominant pattern of Burundi rainfall is the seasonal move of the dominant Intertropical convergence zone (ITCZ), the Congo air mass and the interconnection with EL Nino/Southern oscillation (ENSO) phenomena. Much of Burundi experiences a bimodal seasonal distribution of rainfall with maxima occurring in the March- April and November. The Interannual variability of rainfall in Burundi shows interesting association with atmospheric and oceanic phenomena. We investigate the variability of rainfall using OND (October, November, December) and MAM (March, April, May) precipitation in Burundi du ...PermalinkThe effects of global environmental change, including coastal flooding stemming from storm surges as well as reduced rainfall in drylands and water scarcity, have detrimental effects on countries and megacities in the costal regions worldwide. Among these, Bangladesh with its capital Dhaka is today widely recognised to be one of the regions most vulnerable to climate change and its triggered associated impacts. Natural hazards that come from increased rainfall, rising sea levels, and tropical cyclones are expected to increase as climate changes, each seriously affecting agriculture, water & fo ...PermalinkCameroon is located on the west coast of central Africa. It is home to about twenty millions inhabitants relying upon rain‐fed agriculture for food security. With the increasing pressure of climate change, other activities for sustainable development such as transport, energy, water, livestock and urban settlement are also facing an increasing threat due to extreme climate and weather events. In some cases today’s climate extremes are expected to become tomorrow’s ‘normal’ weather. This assumption stresses the need of understanding the past, the current and hopefully to project local climate b ...PermalinkA bibliographic review of the state of art of flood estimation techniques shows the importance of studying floods as multivariate events. The aim of this work is to discuss whether a multivariate analysis is necessary for designing dams or for assessing the adequacy of spillways belonging to existing dams. A multivariate approach offers a range of possible events associated to a joint return period, which can be used in a design stage. The multivariate criterion includes information related with the dependence structure linking the flood variables. This dependence is involved in the generation ...PermalinkBhutan is classified as one of the forty-eight least developed countries with farmers comprising more than two-thirds of its total population. The agriculture sector, which is a significant contributor to the country’s gross domestic product, has been vulnerable to extreme climate events in recent decades. As an effort to address the potential challenges it will face under climate change, this thesis projects the yields of three primary crops grown in Bhutan, rice, wheat and maize, for the period 2030 to 2050, based on climate projections by the PRECIS regional climate model.
In this st ...PermalinkAimed at understanding the physical mechanisms driving rainfall systems in southern Africa with a particular focus on Zimbabwe, this research is a step towards improving the representation of those systems in Climate Models leading to improved Rainfall projections. Because RCMs such as PRECIS are good at resolving subtle systems which modify local climates and possibly mask the anticipated anthropogenic induced (rainfall) change, its use in regions such as Zimbabwe that have complex terrain is crucial. Understanding the physical mechanisms that control rainfall in the current climate also prov ...PermalinkTo mitigate adverse effects of future extremes in climate in the extreme southern Caribbean and Trinidad and Tobago require a sound understanding of the science of the climate, along with realistic and region specific projection outputs; in order that an effective response can be provided by respective regions. As a step towards achieving this, downscaling GCM outputs through RCMs is useful at the local and regional scales because it can provide finer detailed and more user friendly output required for planning. Moreover, it is an avenue through which more profound understanding of the ...PermalinkSeveral studies suggest that weather patterns over Lake Victoria are highly variable, with wind gusts in the vicinity of thunderstorms suddenly thrashing up high waves capable of capsizing small fishing boats. In order to improve safety on the lake, the Mobile Weather Alert (MWA) service is implemented by utilising mobile phone technology to provide daily weather forecasts that reduces vulnerability of fishermen to weather hazards. This service was developed as a pilot scheme under the WMO Severe Weather Forecast Demonstration Project (SWFDP). An evaluation of MWA forecasts over Lake Victoria ...PermalinkLesotho is a small mountainous country is southern Africa. Lesotho is a temperate region that has four distinct seasons; spring, summer, autumn and winter. It is among countries that are vulnerable to climate change impacts. As such, future climate projections are vital to the country. Lesotho has submitted her first and the only report (FNC) to the United Nations Framework Convention on Climate Change (UNFCCC) in 2000. The report includes vulnerability and adaptation (V&A) assessment developed using the first generation low resolution Global Climate Models (GCMs) output. This study was aimed ...PermalinkUganda has experienced a number of extreme weather and climate events in the form of floods and droughts. In a number of cases, flood events associated with heavy rainfall have been followed immediately by droughts that tend to persist for several seasons. These events have always had devastating impacts on various sectors of the country's economy. The impacts include destruction of infrastructure, loss of life and property and many other far reaching socio-economic impacts. The impact of these extreme events can be greatly reduced through good understanding of previous climatic events and the ...PermalinkThe science of weather forecasting is only as good as its ability to produce results. Models are some of the tools meteorologists have come to depend on to help them in forecasting and the dependability as well as reliability of a model is measured by its ability to track and forecast ahead of time a given event. Thus this study looked at the inter comparison of four models namely; GFS, ECMWF, UKMET and METEOFRANCE models, three of which are mostly used by the forecast offices of the Nigerian Meteorological Agency.PermalinkSujeewa Kanda Durage; Institute of Environmental Science and Meteorology ; College of Science - University of the Philippines, 2011Climatologists and meteorologists in Sri Lanka observe that ground temperature measurements in many weather stations have risen and people are experiencing more episodes of warmer weather. Sri Lanka is a country vulnerable to warming or rise in temperature; in particular its economic development is mostly dependent on agriculture, which can be severely affected by large and abrupt changes in temperature. This study was carried out to detect and characterize changes in surface temperature in the last 140 years, as a precursor of climate change in Sri Lanka. Daily maximum and minimum temperature ...PermalinkBen Mansour Maher; National Oceanic and Atmospheric Administration (NOAA); National Center of Environnement Prediction (NCEP) - NOAA, 2011"To better understand the variability of rainfall in Tunisia, it was evident to treat series of data of around tens years. And to do this I used a set of Fortran programs and scripts Grads to represent a historic of 30 years of daily rainfall over the period 1978-2007 from 12 stations of the observing networks in Tunisia."PermalinkWorld Meteorological Organization (WMO) ; ANAMS ; National Oceanic and Atmospheric Administration (NOAA) - WMO, 2011Severe weather events in West Africa are associated mainly with meso-scale thunderstorms and squall lines. Forecasting such severe weather to reduce the risk of hazards is one of the challenges faced by many met services. However, the recent progress in the area of numerical weather prediction has enabled some countries to forecast these events in a better way.
Due to lack of capacity, many of the West African countries were not able to use numerical weather prediction systems effectively in their day to day forecasting activities. The CPC/African Desk has been playing big role in buil ...PermalinkIn this case study, attempt was made to verify the performances of the TIGGE and WRF models in simulating rainfall over southern Africa for the period from 1st November 2009 to 10th February 2010, with 24 and 48 hrs lead time. We have tested the skills of the models in forecasting heavy rainfall event, in excess of 40mm per day. Special emphasis was given to rainfall event that occurred on the 3rd of February 2010 over Zambia. The associated atmospheric conditions prior and during the rainfall event were also analyzed, both in analysis and forecasted fields.
Over Southern Africa, all th ...PermalinkIntroduction: Model verification is an essential part of a Weather Prediction system. It is a helpful knowledge to enhance the forecaster’s assessment in Weather bulletin production. The aim of this study is to compare the global Forecast system (GFS) model rainfall prediction accumulated for 24 hours and averaged over October, November and December 2008 with the African Rain Fall Estimate (RFE 2.0) (Love et al.,2002) over DRCongo and the neighboring areas (from 15S to 6N latitudes and from 10E to 32E longitudes) fig.0.PermalinkThe objective of this work is thus to enhance an understanding on the regional and global patterns that may contribute to the knowledge of the variability and predictability of OND and JFM rains season over DRC for a better prediction of the rains season and also to improve the DRC seasonal models for a better decisions makers, and also assist potentials users on their needs.PermalinkWorld Meteorological Organization (WMO) ; Institute for Meteorological Training and Research (IMTR) - IMTR, 2006Extreme climate events such as floods and droughts have devastating socio-economic impacts associated with food shortages, famine, lack of energy, water, shelter and other major basic needs. Because these events are recurrent in nature, effective, accurate and timely prediction and early warning of these events can enable Governments and other stakeholders to put into motion appropriate actions for mitigating or alleviating their adverse impacts. In this study, the relationship between seasonal rainfall and global Sea Surface Temperature anomalies was examined. The analysis was based primarily ...Permalink