A platform for research: civil engineering, architecture and urbanism
Spatio-temporal analysis of rainfall trends over a maritime state (Kerala) of India during the last 100 years
Abstract Kerala, a maritime state of India is bestowed with abundant rainfall which is about three times the national average. This study is conducted to have a better understanding of rainfall variability and trend at regional level for this state during the last 100 years. It is found that the rainfall variation in northern and southern regions of Kerala is large and the deviation is on different timescales. There is a shifting of rainfall mean and variability during the seasons. The trend analysis on rainfall data over the last 100 years reveals that there is a significant (99%) decreasing trend in most of the regions of Kerala especially in the month of January, July and November. The annual and seasonal trends of rainfall in most regions of Kerala are also found to be decreasing significantly. This decreasing trend may be related to global anomalies as a result of anthropogenic green house gas (GHG) emissions due to increased fossil fuel use, land-use change due to urbanisation and deforestation, proliferation in transportation associated atmospheric pollutants. We have also conducted a study of the seasonality index (SI) and found that only one district in the northern region (Kasaragod) has seasonality index of more than 1 and that the distribution of monthly rainfall in this district is mostly attributed to 1 or 2 months. In rest of the districts, the rainfall is markedly seasonal. The trend in SI reveals that the rainfall distribution in these districts has become asymmetric with changes in rainfall distribution.
Highlights The rainfall trend and seasonality index is evaluated for Kerala state of India. The trend is evaluated on a monthly, seasonal and annual timescale. The rainfall trend is decreasing significantly in almost all regions. Skewness in rainfall is found in the state by seasonality index test.
Spatio-temporal analysis of rainfall trends over a maritime state (Kerala) of India during the last 100 years
Abstract Kerala, a maritime state of India is bestowed with abundant rainfall which is about three times the national average. This study is conducted to have a better understanding of rainfall variability and trend at regional level for this state during the last 100 years. It is found that the rainfall variation in northern and southern regions of Kerala is large and the deviation is on different timescales. There is a shifting of rainfall mean and variability during the seasons. The trend analysis on rainfall data over the last 100 years reveals that there is a significant (99%) decreasing trend in most of the regions of Kerala especially in the month of January, July and November. The annual and seasonal trends of rainfall in most regions of Kerala are also found to be decreasing significantly. This decreasing trend may be related to global anomalies as a result of anthropogenic green house gas (GHG) emissions due to increased fossil fuel use, land-use change due to urbanisation and deforestation, proliferation in transportation associated atmospheric pollutants. We have also conducted a study of the seasonality index (SI) and found that only one district in the northern region (Kasaragod) has seasonality index of more than 1 and that the distribution of monthly rainfall in this district is mostly attributed to 1 or 2 months. In rest of the districts, the rainfall is markedly seasonal. The trend in SI reveals that the rainfall distribution in these districts has become asymmetric with changes in rainfall distribution.
Highlights The rainfall trend and seasonality index is evaluated for Kerala state of India. The trend is evaluated on a monthly, seasonal and annual timescale. The rainfall trend is decreasing significantly in almost all regions. Skewness in rainfall is found in the state by seasonality index test.
Spatio-temporal analysis of rainfall trends over a maritime state (Kerala) of India during the last 100 years
Nair, Archana (author) / Ajith Joseph, K. (author) / Nair, K.S. (author)
Atmospheric Environment ; 88 ; 123-132
2014-01-25
10 pages
Article (Journal)
Electronic Resource
English
Rainfall trends in twentieth century over Kerala, India
Elsevier | 2008
|Evaluation of CHIRPS Satellite Rainfall Datasets Over Kerala, India
Springer Verlag | 2020
|Taylor & Francis Verlag | 2022
|