CLIMATE CHANGE IMPACTS ON AGRICULTURE WATER MANAGEMENT - PERSIDANGAN AIR MALAYSIA (PAM 2014)
Agriculture is entirely dependent on weather and climate stability. Factors such as temperature, rainfall and drought greatly affect crop yield. Temperature has an inverse relationship with yield at the upper range of the optimum growth curve – which means that higher temperature would lead to a corresponding decrease in yield. Rainfall variability, on the other hand, is a major limiting factor to the many crops including oil palm. At this point, NAHRIM is at the forefront of climate research in Malaysia. NAHRIM has been continuously producing studies based on projections from Global Climate Models (GCMs), on various issues and locations such as climate change impact on dams, coastal areas, floods and droughts. Recent studies conducted by NAHRIM shows climate change impacts in Malaysia can be broadly divided into three types: rainfall, floods and droughts; temperature; and sea level rise. In climate change studies by NAHRIM, surface temperature for Peninsular Malaysia is expected to experience an average increase of 2.72°C from 2010 to 2100, while for East Malaysia, the increase for the same time period is projected to reach 4°C. According to a study on rainfall patterns in Peninsular Malaysia, the 30 years average annual rainfall up to 2100 is expected to increase. The magnitude increase for each area differs, with no obvious trend for each location. The increase in magnitude and intensity will also increase the design rainfall in the future. This will affect peak flow and probably cause more extreme flood events. On the other hand, a few rivers such as Muda in Kedah are expected to have decreased monthly flows and changes to the basins’ wet and dry seasons. This would affect future water availability. For agriculture in Muda Irrigation Scheme, the projected future annual effective rainfall shows an increasing trend up to year 2060; however it still could not meet the projected irrigation water demand. The area will face 106 months of water deficit and 134 months of water surplus. Deficit mainly occurs in the months of March to May and November to January. 13 out of 20 planting seasons will be affected by water deficit from 2025 to 2034 and 17 out of 20 planting seasons from 2041 to 2050, which is mainly due to the low projected monthly rainfall. Dam inflow projections for major irrigation dams such as Muda, Beris and Selangor are analysed for year 2010 to 2050. For every month of every decade, the average dam inflows remain relatively constant for the same month, with slight increase towards mid-century (2040-2050) except for Selangor dam. The estimated average inflow for Muda dam in January and February is expected to be the lowest compared to the rest of the year. The average inflow for Beris dam is expected to be quite low throughout the year but will be relatively high in October and November. The least inflow in Selangor dam will occur during June to July and January to February.
Authors
Abstract
Agriculture is entirely dependent on weather and climate stability. Factors such as temperature, rainfall and drought greatly affect crop yield. Temperature has an inverse relationship with yield at the upper range of the optimum growth curve – which means that higher temperature would lead to a corresponding decrease in yield. Rainfall variability, on the other hand, is a major limiting factor to the many crops including oil palm. At this point, NAHRIM is at the forefront of climate research in Malaysia. NAHRIM has been continuously producing studies based on projections from Global Climate Models (GCMs), on various issues and locations such as climate change impact on dams, coastal areas, floods and droughts. Recent studies conducted by NAHRIM shows climate change impacts in Malaysia can be broadly divided into three types: rainfall, floods and droughts; temperature; and sea level rise. In climate change studies by NAHRIM, surface temperature for Peninsular Malaysia is expected to experience an average increase of 2.72°C from 2010 to 2100, while for East Malaysia, the increase for the same time period is projected to reach 4°C. According to a study on rainfall patterns in Peninsular Malaysia, the 30 years average annual rainfall up to 2100 is expected to increase. The magnitude increase for each area differs, with no obvious trend for each location. The increase in magnitude and intensity will also increase the design rainfall in the future. This will affect peak flow and probably cause more extreme flood events. On the other hand, a few rivers such as Muda in Kedah are expected to have decreased monthly flows and changes to the basins’ wet and dry seasons. This would affect future water availability. For agriculture in Muda Irrigation Scheme, the projected future annual effective rainfall shows an increasing trend up to year 2060; however it still could not meet the projected irrigation water demand. The area will face 106 months of water deficit and 134 months of water surplus. Deficit mainly occurs in the months of March to May and November to January. 13 out of 20 planting seasons will be affected by water deficit from 2025 to 2034 and 17 out of 20 planting seasons from 2041 to 2050, which is mainly due to the low projected monthly rainfall. Dam inflow projections for major irrigation dams such as Muda, Beris and Selangor are analysed for year 2010 to 2050. For every month of every decade, the average dam inflows remain relatively constant for the same month, with slight increase towards mid-century (2040-2050) except for Selangor dam. The estimated average inflow for Muda dam in January and February is expected to be the lowest compared to the rest of the year. The average inflow for Beris dam is expected to be quite low throughout the year but will be relatively high in October and November. The least inflow in Selangor dam will occur during June to July and January to February.
Citation
IR. MARINI MOHAMAD IDERIS , IR. MOHD ZAKI MAT AMIN, GOH YEE CAI, NURUL HUDA MD. ADNAN. 2014. CLIMATE CHANGE IMPACTS ON AGRICULTURE WATER MANAGEMENT - PERSIDANGAN AIR MALAYSIA (PAM 2014). Digital NAHRIM Publication Repository.