Friday, June 21, 2019


One of the most beautiful things on this earth are the oceans, which occupy a large expanse of it! As Indians, we all are proud of our northern protective mountain ranges of Himalayas, which feed seven of Asia’s large and majestic rivers; Ganga, Indus, Brahmaputra, Salween, Mekong, Yangtze and Huang He. Himalayas stand tall with their majestic landscape, rightly known as the ‘Water Towers of Asia’. instilling a sense of awe, wonder and amazement, spanning about 33,000 kms of glaciers. During summer, Himalayas are an important source of water for huge human population. Himalayas are presently facing the effects of climate changes and undesirable human activities and glaciers are retreating. Glaciers contribute up to 75 per cent of river water during summers and their retreat leads to freshwater scarcity during dry seasons, affecting regional agriculture and energy sources. Loss of melting water of glaciers affects downstream water flows, affecting the lives of several million Indians.  
Globally too, this has a large impact!
Since 1880, global average sea level has increased 8 inches, about 7 cms over the last 22 years, due to global, regional, and local factors.
·         Along the East Coast and Gulf of Mexico, path changes and strength of ocean currents have led to fast sea level rise.
·         In East Coast and Gulf regions, subsiding land has led to ocean penetrating inland.
·         Shrinking of glaciers, land ice, ice caps and sheets has speeded up.
·         Loss of land ice has added about half inch to global sea level during 2003 to 2007, leading to 75 to 80 per cent of the increase.
·         The long-term global sea level rise depends on heat-trapping emissions and quick response  of land ice to increasing temperatures.
·         Past heat-trapping emissions of gases will affect rise in sea level up to 2050, present and future emissions will affect it after 2050.
·         We have already affected the environment so badly that even if emissions drop to nil, sea levels will keep rising as oceans and land ice need to adjust to the undesirable changes.
·         The greatest impact will be on rate and magnitude of the loss of ice sheets, in Antarctic regions, due to the atmospheric heat-trapping emissions. 
Changing sea levels are due to different reasons, but climate change is the driving force! 2 degree rise in temperature would lead to sea rise by 0.4 to 1.4 meters due to thermal expansion. Melting ice sheets add to the total amount of water in the world’s oceans, predicting a sea rise by 19 to 59 cm by 2100.
As the earth heats, sea water warms up taking up more space causing thermal expansion. Melting glaciers and ice sheets add even more water into the oceans, leading to a rise in sea level.
In winter, snows balance melting. Today, global warming has resulted in continuously elevated temperatures causing above average melting, less snowfall causing imbalance and rise in sea levels.
Massive ice shelves are weakening and breaking off because of melting. Increase in ocean's mass leads to a global sea level rise of 1.9 mms each At this rate, 6.4 meters sea level rise may be expected in upcoming years. Irreversible melting already occurred may require hundreds of years to reverse.

Rising sea levels lead to;
·         Higher risks of erosion and floods,
·         Damage to manmade infrastructures,
·         Disturbing of delicate coastal ecosystems
·         Flooding threatens human health with water-borne diseases
·         Rising sea water contaminates agricultural land
·         Rising sea water contaminates drinking water.
·         Erodes shorelines
·         Causes loss of wetland
·         Allows salt water to enter fresh water bodies
·         On penetrating inland, it may lead to destructive erosion
·         Flooding of wetlands
·         Contamination of aquifers and agricultural soils,
·         Disturb habitat for fish, birds, plants.
·         Large storms can submerge low-lying islands
·         Coastal areas may be disproportionately affected due to ocean currents.
·         This may disturb homes and livelihoods of people in coastal areas of the globe.

·         Burn no or fewer fossil fuels.
·         Curb emissions of certain pollutants
·         Reduce emissions of methane, tropospheric ozone, hydro fluorocarbons and black carbon, specific pollutants which may prevent rise in sea level by about 25 to 50 per cent.
·         Cut back on motor vehicle exhaust
·         Curb industrial emissions, chemical solvents, windshield washer fluid, create fewer CFCs
·         Cut back on smoke or soot generating activities.

Many countries have managed rising sea levels by;
·         Construction of sea defences such as dams and other barriers.
·         Coastal armouring is used to raise and fix shorelines in place, through seawalls or levees. Infrastructure could be designed to be elevated or buoyant to deal with rising waters.
·         Developing and nurturing coastal biomes is a good protection against rising sea water. Ecosystems such as wetlands and mangrove forests protect shorelines from erosion.

In vulnerable areas, well-managed migrations and early-warning flood systems are needed to help people threatened by rising sea levels.
Over the long term, scientists warn that the only way to limit sea level rise will be to drastically reduce emissions of the greenhouse gases dangerously warming the planet, though already significant irreversible damage has been done.

We tend to attribute all this to "climate change", which is deceptive! We should now pledge to stop using the term “climate change” and start using the words  increasing global warming or disturbed climate to describe the destruction caused by global warming primarily due to human activities like burning of fossil fuels.

The choices we make today, the life style we adopt today, the habits we inculcate in ourselves today, will determine how the sea level rises this century, how fast it occurs and how much time we really get to protect our communities!
Dr. Mrs. Jaya Vikas Kurhekar,
Green Blogger