Impacts of Climate Change and Global Warming

Climate change is defined as average change in weather conditions (temperature, precipitation, humidity, etc.) of a region over a minimum period of 30 years.

Global warming is defined as increase in average temperature of Earth (from the current 15 °C) due to the increase in concentration of Greenhouse Gases.

Impacts of Climate Change and Global Warming

Climate change and global warming are likely to have many manifested effects on the human communities, biodiversity, agriculture and economy. Some of such major impacts are:

1. Melting of Polar Icecaps and Sea Level Rise

The increasing temperature levels as a result of global warming and climate change are likely to result in accelerated melting of glaciers and ice in Arctic and Antarctica and consequently increase in average sea level of Indian, Atlantic and Pacific oceans. A sea level rise of just 1 m would be sufficient enough to completely submerge the low-lying islands such as Maldives, Mauritius, Fiji, etc. The increased sea levels would also lead to the intensification of water cycle and increased frequency of floods, cloudburst, cyclones, typhoons and hurricanes all around the world. Besides the Arctic and Antarctica, global warming is also likely to lead to loss of ice and glacier covers in the major mountain system such as Andes and the Himalaya. The loss of glacier cover in the headwaters of these major mountain systems would result in reduced water flow in the rivers flowing from these mountains such as Ganga, Brahmaputra and Indus.

2. Loss of Biodiversity

Global warming and climate change are one of the most predominant drivers of biodiversity loss all around the world, leading to extinction and extermination of species. Species that are likely to suffer the highest risk are the ‘endemic species’ (species found only small restricted localities), ‘migratory species’ (species that migrate long-distances from one place to the other), ‘alpine species’ (species that are found on the top of the mountains) and ‘specialist species’ (species that are found only in one kind of climate). Some of such species are penguins, polar bears, pandas, snow leopards, purple frog, monarch butterflies, Himalayan yaks, etc. These species are unlikely to adapt to the changing climate conditions and are likely to go extinct such as the Dinosaurs. Even coral reefs – underwater ecosystems that harbor greatest biodiversity of ocean fishes and marine organisms and provide one of the largest ecosystem services on Earth, are facing collapse due to ‘coral bleaching’ – a phenomenon in which the coral dies and turns white in color due to increasing temperature and acidification of oceans. Half of the Great Barrier Reef of Australia is already dead due to the phenomenon of coral bleaching.

3. Impact on Agriculture

Climate change is likely to have significant impacts on agriculture of a given region leading to decrease in productivity and shifts in cropping patterns in tropical biomes while increasing agricultural productivity in temperate biomes. However, it is likely to lead in disproportionate shifts in cropping patterns all over the world. For example, in India the patterns of Rabi and Kharif seasons are likely to change by at least one month. Climate change would also lead to widespread proliferation and dispersal of non-native pests and exotic invasive species such as Parthenium, Lantana, Prosopis and Conyza that would lead to invasion of agricultural lands and decrease soil fertility and agricultural productivity of a region.

4. Impact on Human Health

Climate warming and increased temperature and humidity levels are likely to help in the widespread proliferation of vector-borne diseases such as malaria, dengue, schistosomiasis, yellow fever, etc. besides food and waterborne diseases. The 2003 heat wave in France resulted in approximately 15,000 human deaths.

5. Impact on Economy

Documentation of the impacts of climate change on economy is difficult due to multiple interrelated direct and indirect effects. However, some reports such as that of International Labour Organization (ILO) indicated that climate change would lead to loss of approximately 2.2% of working hours every year, 80 million full time jobs and 2,400 billion US dollars. Economics costs due to climate change would also rise in terms of health cost, infrastructure, insurance and energy costs. Fisheries, that constitute important source of livelihoods for millions of people all around the world are also likely to be significantly impacted leading to monetary and employment losses.