“Climate change means the change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods” – UNFCCC

Climate change, also called global warming, refers to the rise in average surface temperatures on Earth. An overwhelming scientific consensus maintains that climate change is due primarily to the human use of fossil fuels, which releases carbon dioxide and other greenhouse gases into the air.

Hence, Climate Change is defined as statistically significant changes in the distribution of weather patterns with the change lasting for long period of time. The changes are in terms of temperature, precipitation, etc.

Predicted changes in Earth's surface temperature

 

Global temperature under different scenarios

If the inaction continues (RCP 8.5), global temperature is expected to increase by 4oC by the turn of this century. The increase is disastrous for agriculture, food security, health and other vital issues

Evidences of Climate Change

• Altered hydrological systems due to changing precipitation patterns and melting snow. This is affecting the quality and quantity of water resources in many regions round the world.

Situation in three important river basins in India: Baseline & Future

River Basin
Baseline (1961-1990) Future (2071-2100)
Annual Rainfall (cm) Annual Flow (km3) Annual Rainfall (cm) Annual Flow (km3)
Ganga 134 482 150 543
Krishna 91 60 112 67
Godavari 166 98 201 116

• Changing habitats is negatively impacting the ecosystem and biodiversity of different regions across the world.

Situation in three important river basins in India: Baseline & Future

• Flora and Fauna of Eastern Himalayas are becoming endemic

• Many species in Arunachal Pradesh and other North Eastern States are extinct or facing extinction

• Cheer Pheasants (Catreus wallichi) are on the verge of extinction

• Ladakh Snow Trout (Gymnocypris biswasi) is almost extint

• Decreased agricultural productivity/yield

Climate Change Impacting Agriculture

• Decreasing production of wheat in most wheat growing regions – the size of the grains and the number of grains per inflorescence decreases

• Reduction of yield in all rain-fed crops

• Temperature Increase is found to reduce yield in Rice Production: Eastern India is particularly vulnerable

• Irregular and untimely precipitation is found to damage agricultural and horticultural crop

• Negative health impacts in terms of increased heat and cold related morbidity and mortality, higher incidences of vector borne and water borne diseases.

• Increased incidences and frequency of extreme events like floods, droughts, cyclones, heat waves, wild fires, etc. resulting in livelihood loss, increased health impacts, mortality, infrastructure damage, threat to food security, etc.

• Increased marginalization of the already marginalized community due to high vulnerability and exposure risks to climate change impacts.

Different effects of climate change

India is expected to have significant and adverse impacts on agriculture, livelihoods, health and many other sectors of the economy. Hence, climate change can have serious consequences on the economy and society with inter-regional equity disturbed.

Climate change is phenomenon which cannot be stalled! The historical and present level of emissions due to anthropogenic activities (along with certain geo-physical factors) has triggered the process. However, we can definitely act to slower the rate of climate change. Scientists have come up with two important actions:

Mitigation

All actions that are aimed at reducing the level of greenhouse gas emission from different activities (energy generation, transport, agriculture, etc.). This calls for introduction of changing structures of economic activities, introduction of novel and new technologies for improving efficiency with respect to emission and/or energy consumption, etc.

Adaptation

Since, in the foreseeable future the impacts of climate change will continue to affect societies and economies, action must be directed at increasing resilience and lessening the impacts. This could be done through awareness generation, introducing technologies, etc.