Tag Archives: Wind speed

The Nexuses between Wind and Rainfall Patterns: Using Wind to Predict Rainfall for Enhanced Adaptability to Rainfall Related Hazards (Published)

The ability to predict rainfall patterns is crucial for making informed decisions on proper adaptation to extreme climatic events like floods and droughts. This study assessed ways through which wind direction and speed could be used to predict the nearness of the beginning and end of the rainy season and the amount of rainfall expected to be received during the rainy season. The study was conducted in Mwanga District in Kilimanjaro Region, Tanzania. It used local perceptions on the nexus between wind and rainfall patterns collected through structured and in-depth interviews involving 110 and 19 respondents, respectively. The local perceptions were corroborated with findings from data on rainfall and wind of the period from 1962 to 2021. It was found that wind tended to blow from the east most of the time and from the south during the long rainy season. Farmers can use the direction of wind to predict the nearness of the beginning and end of the rainy season. If they find that wind blows from the abnormal direction at the beginning of the rainy season, they conclude that the rainy season is yet to begin. Besides, if wind continues blowing from the abnormal direction, after the rainy season has begun, they conclude that rainfall will be less than normal. Further, occurrence of cyclones during the dry season indicates that the short rainy season will start soon. If the frequency of the cyclones is high, then heavy rains will be received. Thus, wind is an important element of weather that could be used to predict the beginning and end of the rainy season as well as the amount of rainfall that will be received. It is, therefore, important that this local knowledge is formally recognized so that it can be used by as many people as possible. Moreover, the local predictions of the pattern of rainfall based on wind should be integrated with modern forecasts to improve the reliability of the predictions at local level. This will lead to the making of informed decisions on adaptation to rainfall-related hazards, and improvement of adaptability and resilience to such hazards.

Citation: Lusiru S.N.  (2023) The Nexuses between Wind and Rainfall Patterns: Using Wind to Predict Rainfall for Enhanced Adaptability to Rainfall Related Hazards, International Journal of Weather, Climate Change and Conservation Research, Vol. 9 No. 1, pp. 1-14


Keywords: Prediction, Rainfall Patterns, Wind direction, Wind speed, adaptability

Construction and Comparative Study of a Standalone Savonius and Darrieus Vertical Axis Wind Turbine (Published)

In this work, a Savonius Vertical Axis Wind Turbine (VAWT) and its Darrieus counterpart was designed and constructed based on a preliminary study involving wind pattern analysis of an identified study area, the Usmanu Danfodio University, Sokoto, Nigeria. The turbines were constructed using wood and metals and the resulting blades were field tested under various wind conditions available in the study area. The results of the test were compared in terms of start-up wind speed and their rotor’s Revolution Per Minute (RPM) values. The result of this test showed that the Savonius rotor proves to self-start at a wind speed of 2.46 ms-1 with a minimum Revolution Per Minute (RPM) of 46 and maximum RPM of 89 at a wind speed of 9.28 ms-1. The Darrieus blade proves to self-start at a higher wind speed of 3.8 ms-1 with a minimum RPM of 54 and a maximum RPM of 93 and at a wind speed of 8.9 ms-1 under same prevailing atmospheric conditions of the study area.  When both standalone results were integrated into a single system, an equivalent of a combined Savonius-Darrieus type of VAWT resulted and for which a reinforcement in RPM was observed.  It was recommended that a combined Darrieus and Savonius VAWT when constructed will optimize the high rotational efficiency of Darrieus and the high self-starting capabilities of Savonous VAWT.

Keywords: RPM, Renewable Energy, Wind Turbine, Wind speed, darrieus, savonius

Calculating the Wind-Chill Index for Selected Stations in Iraq (Published)

The Wind-Chill Index (Ko) is used to express a sense of human comfort depends on where the wind speed and temperature together, if considered the human body is a thermal machine liberate energy on an ongoing basis anything that affects the heat loss from the body, which in turn affects the nature of the sensation rate warming to his body and thus affect the rest, and can predict all sense of human beings too hot or cold through calculate the Wind-Chill Index. The aim of this research to clarify the relationship between air elements of each of the temperature and wind speed, can be human comfort through calculate the Wind-Chill Index, using temperature and wind speed data for the period (2005-2015) of the general body from the Iraqi meteorological organization and seismology for selected stations in Iraq (Mosul, Baghdad and Basra), by using of statistical sophisticated programs (Simple Linear Regression and Spearman Rho Test), It was found that the monthly average calculation for the period of the study Wind-Chill Index that the highest value for the index were in Baghdad station 642.47W/m2 for the month JAN, and it found that the lowest value was in Basra station -193.26W/m2 for the month JUL, and found when the seasonal average for calculate the Wind-Chill Index, the winter has high values in addition to the month MAR also has high values in the Mosul and Baghdad stations, except Basra station the month MAR is considered ideal, either for the summer months, it owns and lowest values in Basra and Baghdad stations, where he extends decline to include the month of MAY of the spring and the month SEP of autumn, either Mosul station, the decreasing values includes the month SEP of all autumn, but the rest of the months illustrates months close to human comfort, except Baghdad station the month NOV is a cool, also found through analysis the annual average for Wind-Chill Index the highest value was in Mosul station 288.53 W/m2 in 2013, the lowest value of Basra station 146.45W/m2 in 2015, and found through the statistical operations between temperature and Wind-Chill Index that there is a strong inverse relationship degree of correlation -0.99, as well as the relationship between wind speed and Wind-Chill Index, is a strong inverse relationship, Medium and low in Mosul station reverse correlation is weak the rank correlation -0.252, the station Baghdad high inverse correlation degree of correlation -0.748, while the Basra station, it is an inverse relationship to moderate correlation -0.594.

Keywords: Human comfort, Iraq, Spearman Rho Test, Temperature, Wind speed