Seminar presented by Dr. Jose George Pottakkal
Climate Change and Its Impacts
Climate is ‘Average Weather’ or it is ‘weather averaged over a long period’, the standard averaging period being 30 years. More rigorously, climate is defined as the statistical description of the mean and variability of relevant quantities over a period ranging from months to thousands or even millions of years. These quantities are most often surface variables such as temperature, precipitation, and wind. However, in a wider sense, Climate is the state, including a statistical description, of the climate system.
In a sense, to the nonprofessional of earlier generations, climate seemed to be unchanging over centuries unlike weather, which changed from day to day. That is no longer the case now – even the public has begun talking about climate change. When I began to work on the retreat of Himalayan glaciers in the year 2000, most people did not take the threat of anthropogenic climate change seriously. However, over the years, we have come to a point where most people believe that the earth’s surface has been warming at a pace that has no parallel in history. The first thing that comes to notice is that the first two decades of the 21st century have been warmer than the ten decades that made up the 20th century.
Then what exactly is climate change? It is the rapid increase in earth’s surface temperatures at global scale predominantly attributed to human activity. Climate change is a complex global challenge driven by various factors, prominently carbon emissions, volcanic eruptions, and solar radiation. Human activities, notably fossil fuel combustion, deforestation, and vehicular pollution, have intensified this issue. These changes lead to more frequent and severe extreme weather events, posing a severe threat to biodiversity.
The environmental impacts of climate change are becoming increasingly evident. However, due to the complexities of multiple drivers and processes at work influencing the climate cycle, there can be time lags between climate change and climate drivers with considerable geographic variability. Rising temperatures are seen as some evidence of environmental change, and this has begun to lead to significant effects on water resources and will have serious growing consequences over time. In our analysis of air temperatures in Upper Chenab Basin of the Western Himalayan Region (WHR), it was observed that mean annual air temperatures during 2000-2020 varied between -9.1 to -11.3oC giving a mean temp. of -10.4oC for the first two decades of 21st Century, while the mean temperature for 1950-2020 was -10.7oC. Though this temperature rise is small, it is significant and resulted in accelerated melting of glaciers of the Upper Chenab Basin. Chhota Shigri Glacier, which has the longest glaciological mass balance record in all of the Hindukush Karakoram Himalaya (HKH) is one example of the complex impact of Climate Change on Himalayan glaciers.
Climate Change Impact on Water
Recent years have witnessed an upsurge of worldwide interest in the potential impacts of climate change on water resources. Climate change is often entwined with alteration of water quantity as well as quality, aggravating the fast-growing water crisis. Over the past few decades, the negative effects of climate extremities are reflected in hydrological cycle, viz., pronounced shifts in global precipitation patterns and increased atmospheric water vapor content, glacier melting, floods, soil erosion, and drought, etc. This situation substantially hinders the progress toward the attainment of Sustainable Development Goals (SDGs), thus jeopardizing the needs of future generations. It is therefore necessary to scientifically address the water security issues triggered by the escalating atmospheric and ocean temperatures.
Climate change has disrupted water systems worldwide, leading to extreme rainfall patterns that cause floods and droughts in various regions. The melting of glaciers due to rising temperatures exacerbates the issue, contributing to rising sea levels. However, there is a call for scrutinizing the current knowledge gaps in climate change vis-à-vis its implications on water resources. The Intergovernmental Panel on Climate Change (IPCC) fourth assessment report forecasts that freshwater resources will be reduced by 10–30% in many arid central tropical parts of the world and that rising sea levels expected to rise by 2080 as a result of climate change. Thus, the repercussions of climate change on water resources are too drastic to be ignored. According to the prediction by IPCC’s AR5 report (IPCC, 2014), atmospheric temperatures could rise globally by 4°C by 2100, which in turn will significantly affect global water supply and water demand. The combined impact of water supply and demand is expected to increase the gaps in demand for water supply, which exacerbates current water management challenges. Climate change may affect groundwater resources due to the expected changes in rainfall and evapotranspiration and spatio-temporal distribution of these important components of water balance. Increased rainfall will lead to higher levels of water flow, increased risk of flooding, and reduced levels of groundwater runoff. Rising temperatures result in higher evapotranspiration, and, in turn, increase the demand for irrigation water, which is already a major consumer of water under current conditions. For water management to be able to meet future challenges, the impact of climate change on water levels needs to be calculated from the regional scale to the area scale.
All the world’s water comes from the oceans and returns there via evaporation, condensation, precipitation, transpiration, surface water runoff, and groundwater flow. This is known as the hydrologic or water cycle. It is an axiom that water on earth, otherwise called water planet, remains the same in terms of total quantity through the ages. However, in which segment of the water cycle it is found or which geographical distribution is highly variable, and this variability is and uneven distribution in on the rise.
Precipitation plays a crucial role in sustaining life on Earth. Considering the population dependence on precipitation, the monsoon dynamics response to increased Greenhouse gas (GHG) concentration in the atmosphere is a problem of both scientific and social relevance. India’s freshwater resources are mainly dependent on the southwest monsoon. As a result, meeting the water needs of agriculture, industry, domestic consumption, energy sector and the environment depends on the monsoonal system. More than 80% of the annual rainfall occurs during monsoon season, i.e. June-September. Therefore, any change in climate, especially during the monsoon season in India, could have a profound effect on agricultural production, which is now under pressure due to high population growth and problems related to water resource management. The intensification of the water cycle, especially by way of an increase in extreme rainfall events coupled with a reduction in the number of rainy days, needs to be factored in while working out adaptation plans at various scales. Cloudburst (rainfall rate >100 mm/hr) events that lead to landslides and flash-floods are strongly associated with global warming and were reported for the first time in Kerala by CUSAT meteorological observatory, Kalamassery in monsoon season.
Surface water resources are significantly altered because of changes in climate variables viz., temperature, precipitation, evapotranspiration, etc. Streamflow, an integral component of the water cycle, is very sensitive to varying climates and could impact water availability even more in the future, especially in the pre-monsoon season. Another aspect is the impact on water quality due to increased temperatures coupled with shifts in precipitation that affect the dilution and mobility of pollutants and kinetics of solute acquisition reactions in rivers and other surface water bodies. Climate change also affects groundwater resources in terms of both quantity as well as quality. Climate forcing could influence rates of soil infiltration, percolation, and subsequently groundwater recharge as well as evaporation in a region, further restricting the replenishment rate of groundwater. For example, Groundwater storage depletion at the rate of 1.25–2.1 cm yr–1 was observed in the Ganges Basin.
Water Scarcity on the Water Planet
It is well known that Planet Earth, known as the Water Planet, is a life-sustaining environment due to the presence of water. So much so, the saying goes, ‘Water is Life’. However, most terrestrial life including human life is inextricably bound with access to freshwater of requisite quantity and quality. That is why almost all ancient civilizations flourished along river valleys, where freshwater supply was abundant, and died down when these freshwater sources dwindled down. Let us consider some of the facts of this unequal distribution of freshwater on earth. It is a well-known fact that globally, 2.1 billion people live without safe water at home. One in four primary schools has no drinking water service, and pupils use unprotected sources or go thirsty. More than 700 children under five years of age die every day from diarrhea linked to unsafe water and poor sanitation. 80% of the people who have to use unsafe and unprotected water sources live in rural areas. Women and girls are responsible for water collection in eight out of ten households with water off-premises. For 68.5 million people who have been forced to flee their homes, accessing safe water services is highly problematic. 159 million people collect their drinking water from surface water, such as ponds and streams. 4 billion people – nearly two-thirds of the world’s population – experience severe water scarcity during at least one month of the year. 700 million people worldwide could be displaced by intense water scarcity by 2030. The wealthier generally receive high levels of WASH (water, sanitation, and hygiene) services at low cost, whereas the poor pay a much higher price for a service of similar or lesser quality.
Then how about our country India? India has 16 % of the world’s population, but only 2.5 % of the world’s land area and 4 % of the world’s water resources. According to a World Bank Report, 1997 water demand, which was 552 bcm in 1997, is expected to reach 1050 bcm by 2025. While the water supply in the first decade of 21st century was ~740 bcm (McKinsey report, 2009), the per capita availability, which was >5000 cum/yr in 1947 reduced to <2000 cum/yr in 1997 and is expected to further reduce1500 cum/yr by 2025, indicating conditions of water stress for many. 20 major river basins are below the water scarcity threshold (1000 cubic metres/yr.). By 2030, water demand will be ~1.5 trillion m3, principally driven by population growth and domestic need for rice, wheat and sugar. Thus, water resource management has an obvious impact on a wide range of policy sectors, including energy, health, food security, and environment. Hence, practitioners need to design appropriate adaptation and mitigation strategies across diverse water-dependent sectors.
Strategies for Adaptation, Mitigation, and Water Security
Researchers attribute much of this change to human activities over the past few decades. To mitigate climate change and maintain a healthy environment on Earth, it is imperative to control human influences. This requires a collective effort to reduce carbon emissions, adopt sustainable practices, and prioritize environmental conservation. Preserving the planet’s climate is a shared responsibility, and it is essential to work together to secure a sustainable future for our world and its inhabitants. Climate action, as outlined in the Paris Agreement, is a crucial step in addressing this global crisis. Given the frequent annual cycle of heat waves followed by extreme rainfall, it is imperative to adopt a ‘Green Lifestyle’ to reduce carbon emissions and avert climate crisis. This involves reducing our carbon footprint through environment-friendly buildings, energy, diet, manufacturing, agriculture, etc. It also involves judicious use of freshwater in our households to conserve this precious resource.
In March 2023, the Minister of State for Jal Shakti, Government of India, informed the parliament that the average annual water availability of any region or country is largely dependent upon hydro-meteorological and geological factors. However, water availability per person is dependent on population of a country. Based on the study titled “Reassessment of Water Availability in India using Space Inputs, 2019” conducted by Central Water Commission, the average annual per capita water availability for the year 2021 and 2031 has been assessed as 1486 cubic meter and 1367 cubic meters respectively.
‘Water’ being a State subject, steps for augmentation, conservation, and efficient management of water resources which positively impact over the issue of per capita water availability are primarily undertaken by the respective State Governments. To supplement the efforts of the State Governments, Central Government provides technical and financial assistance to them through various schemes and programmes.
The government of India, in partnership with States, has been implementing Jal Jeevan Mission (JJM) since August, 2019 to make provision of tap water supply to every rural household in the country. At the time of the announcement of the Mission, only 3.23 Crore (17%) of rural households had a tap water supply. Since the launch of the Mission, more than 8.25 Crore have been provided with tap water connection as on 20.03.2023. Thus out of 19.42 Crore rural households, around 11.48 Crore (59.15%) rural households are presently getting tap water supply.
The government of India launched the Atal Mission for Rejuvenation and Urban Transformation (AMRUT) in 2015 which focuses on the development of basic urban infrastructure especially water supply and access to tap connection to every household in 500 cities. Taking it forward, AMRUT 2.0 was launched in 2021, which covers all the statutory towns of the country to ensure universal coverage of water supply & make cities ‘water secure’. For water availability & conservation, so far, 2,996 water supply projects have been approved by Apex Committee at Ministry of Housing and Urban Affairs.
To ensure optimum utilization of water, the Government of India has been implementing Pradhan Mantri Krishi Sinchayee Yojna (PMKSY) from 2015-16 onwards. Under PMKSY-Accelerated Irrigation Benefit Programme (AIBP), 99 ongoing major/medium irrigation projects were prioritized during 2016-17, in consultation with States. Out of these projects, AIBP works of 50 prioritized projects have been reported to be completed. An additional irrigation potential of 24.35 lakh hectares has been reported to be created by these projects in the country, during 2016-17 to 2021-2022. The extension of PMKSY for the period 2021-22 to 2025-26 has been approved by the Government of India, with an overall outlay of Rs. 93,068.56 crore. The scheme of Surface Minor Irrigation (SMI) and Repair, Renovation & Restoration (RRR) of Water Bodies has now become a part of PMKSY-HKKP.
The Mission Amrit Sarovar was launched on National Panchayati Raj Day on 24th April, 2022 as a part of celebration of Azadi ka Amrit Mahotsav with an objective to conserve water for future. The Mission is aimed at developing and rejuvenating 75 water bodies in each district of the country.
Jal Shakti Abhiyan-I (JSA-I) was conducted in 2019 in 1592 blocks out of 2836 blocks in 256 water-stressed districts of the country and was expanded as “Jal Shakti Abhiyan: Catch the Rain” (JSA:CTR) in 2021 with the theme “Catch the Rain – Where it Falls When it Falls” to cover all the blocks of all districts (rural as well as urban areas) across the country. “Jal Shakti Abhiyan: Catch the Rain” (JSA: CTR) -2022 campaign, the third in the series of JSAs, has been launched on 29.3.2022 to cover all the blocks of all districts (rural as well as urban areas) across the country. Now, JSA: CTR 2023 has been launched by the Hon’ble President of India across the country and implemented during the period from 04.03.2023 to 30.11.2023.
Jal Shakti Kendras has been established in 632 districts across the country by March 2023 and counting. More than 264 districts have prepared water conservation plans. The Bureau of Water Use Efficiency (BWUE) has been set up for the promotion, regulation, and control of efficient use of water in irrigation, industrial and domestic sectors. The Bureau will be a facilitator for the promotion of improving water use efficiency across various sectors namely irrigation, drinking water supply, power generation, industries, etc. in the country.
Central Ground Water Board is periodically monitoring the groundwater levels throughout the Country on a regional scale, through a network of monitoring wells. To assess the decline in water level on a long-term basis, the water level data collected by CGWB during November 2022 has been compared with the decadal average (2012-2021). Analysis of water level data indicates that about 61% of the wells monitored have registered a rise in groundwater levels. The rise in groundwater level is the cumulative effect of the both Central and State Government initiatives.
The government of India is implementing Atal Bhujal Yojana (ATAL JAL), a Central Sector Scheme with an outlay of Rs 6000 crore in identified water-stressed areas of 8220 Gram Panchayats (GPs) under 229 blocks in 80 districts of Seven States viz. Gujarat, Haryana, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan, and Uttar Pradesh to arrest decline in ground water level through community-led sustainable groundwater management. The scheme is being implemented from 01.04.2020 for 5 years.
Central Ground Water Authority (CGWA) has been constituted under Section 3(3) of the “Environment (Protection) Act, 1986” for the purpose of regulation and control of groundwater development and management in the Country. CGWA grants No Objection Certificates (NOCs) for ground water abstraction to Industries, Infrastructure units and Mining projects in feasible areas in certain States/UTs where regulation is not being done by the respective State/UTs. CGWA also issues notifications and directions to State Governments and the Administrators of the UTs to adopt Roof Top Rain Water Harvesting (RTRWH) in all the ‘Critical’ and ‘Over-exploited’ assessment units (blocks / Taluks / Firkas / Districts / Valley / Islands / Region / Tehsil, etc. in the country and in all the Government buildings under their jurisdiction.
A nationwide census of natural water springs is in the anvil, National Institute of Hydrology having been chosen as the nodal agency in collaboration with CGWB and other Central and State/UT agencies working in tandem to create spring inventory aimed at rejuvenating these ‘water pigmies’.
Think Globally, Act Locally As we have seen in the previous sections, Climate Change is a global phenomenon, its negative impacts manifest variably in different geographical regions and hydro-climatic regimes. We also saw how the government of India in association with State Governments is making significant efforts Thus the strategies to be adopted at local levels will depend on the specific “Jal Shakti Abhiyan” and “Catch the Rain 2024” campaigns to ramp up water security at the local level in each district and block in the country. While acknowledging that the world is one big family (Vasudevakudumbakam), and the problem is global in scale, we must act locally to ensure that not only we, but also our succeeding generations have access to adequate quantity of requisite quality freshwater resources. One area that we can give our mite is in roof top harvesting of rainwater. Let us “Catch the Rain” for water conservation in our locality. The critical role of women in ensuring water security is embedded in the tagline “Nari Shakti Se Jal Shakti”. I hope Thannissery Panchayat may take a lead in this endeavor to harvest rainwater that God so abundantly has given us in ‘God’s own country’ to sustain life in this land.
