Glacier melt in the Himalayas today is twice as fast as it was before 2000. With conditions remaining unchanged, the glaciers are likely to lose two-thirds of their total ice.
Images, once secret, from Cold War-period US spy satellites helped find out the fact.
Hexagon, a US spy program in the 1970s-’80s, launched 20 satellites to photograph secretly our world including the Himalayas. The US Geological Survey digitized the images after declassification in 2011 for scientists.
Scientists compared the photographs with recent spacecraft data from NASA and Jaxa, the Japanese space agency. Thus, they found the changes in the glaciers.
The study result – “Acceleration of ice loss across the Himalayas” – has been published in the journal Science Advances (June 19, 2019, vol. 5, no. 6).
The scientists have found that melting in the region has doubled over the last 40 years. Since 2000, glaciers’ heights have been shrinking by an average of 0.5m per year. The scientists say that climate change is the main cause.
Led by Josh Maurer, graduate student of Columbia University, the researchers checked 650 large glaciers in the Himalayas spanning 2,000km. Other researchers are J. M. Schaefer, S. Rupper and A. Corley.
The scientists found that between 1975 and 2000, an average of 4bn tons of ice was being lost each year. But, between 2000 and 2016, the glaciers melted approximately twice as fast, losing about 8bn tons of ice each year on average.
The losses varied by region. But, the trends were broadly consistent across the entire region the scientists examined.
The findings broadly support other recent studies of retreating Himalayan glaciers.
The Hindu Kush Himalaya Assessment: Mountains, Climate Change, Sustainability and People (Philippus Wester, Arabinda Mishra, Aditi Mukherji and Arun Bhakta Shrestha (ed.)) report projected that even in the best-case scenario the Himalayas are very likely to lose a-third of its total ice by the end of the century. The best-case scenario is: A world with carbon-neutral level by 2050 by rapid decarburizing, and limiting global warming to 1.5 degrees Celsius. The report, published in February 2019, is by the International Centre for Integrated Mountain Development, Kathmandu, Nepal.
Scientists say continued glacial ice losses would have wide impact that includes increase in meltwater altering hydrology, causing floods, disrupting water supplies and hydropower.
For a poverty- and inequality-ridden region with a population of about 1.6 billion, this loss of glaciers will be catastrophic as the vast region below the Himalayas depends on rivers fed by the glacier meltwater during the summer.
The glaciers are also a major source of fresh water for ecosystems in the region; and millions of people depend on these ecosystems. The glaciers supply around 800 million people with water for irrigation, hydropower and drinking. They would face difficulties in many areas of life and economy including agriculture.
And, in this case, the poor will suffer most although they consume least and their carbon-foot print is the tinniest while the rich consume the most, their carbon-foot print is the biggest, and the system the rich have build up to only serve them is the source of degradation of environment and ecology, and rising temperature in the world.
Farooque Chowdhury writes from Dhaka.
“… the poor will suffer most although they consume least and their carbon-foot print is the tiniest while the rich consume the most, their carbon-foot print is the biggest, and the system the rich have build-up to only serve them is the source of degradation of environment and ecology, and rising temperatures in the world.”
Yes, this is one of life’s ironies: the work of the many poor sustains the comfort of the rich few. In other words, the poor sustain the system that keeps them poor.
So the ice melts.
WHY? Because planet earth heats.
WHY? Because energy is being produced faster than it can be dissipated through the earth’s atmosphere.
HAS IT ALWAYS BEEN LIKE THIS? No, only since the Industrial Revolution and the use initially of steam engines, that is, approximately over the last 200 years.
WHY? The Industrial Revolution replaced ‘animal muscle power’ and ‘natural wind and water power’ with ‘chemical power’ (by burning fossil fuels).
WHAT ARE ‘FOSSIL FUELS’? Basically, hydrocarbons found in the earth’s suface in the form of coal, peat, oil and gas. These can be burnt (combusted) to liberate energy, mainly as heat and light. Water and carbon dioxide (CO2) are also formed.
HOW? Because hydrocarbons used the oxygen of the air to form water (H2O) and CO2, liberating heat (and light) energy that can be used for other purposes, i.e the Industrial Revolution.
HOW ARE FOSSIL FUELS FORMED? They are formed in the earth’s surface over hundreds of millions of years from decaying plant material that once covered much of the surface.
WHERE DOES THE ENERGY COME FROM? From the sun, in the form of radiant energy. In one of Life’s miracles, in green plants the sun’s radiant energy causes water and carbon dioxide from the earth’s atmosphere to form sugar (C6 H12 O6 ) with oxygen gas being liberated into the atmosphere (enabling animal life). Thus sugar contains the captured energy of the sun. It is largely stored in the form of cellulose. When the plant dies, it slowly converts into hydrocarbons in the earth’s surface. Some of the sun’s energy is thus stored as hydrocarbons in the surface of the earth and has remained there over hundreds of millions of years in a chemical equilibrium that has allowed life to flourish and diversify.
If we have burnt half of the earth’s hydrocarbons, then in 100 years we have used about 100 thousand years of captured energy from the sun.
IF THE SUN’S ENERGY COMES TO EARTH, WHY CAN THE EARTH’S ENERGY NOT RETURN TO SPACE? Because the sun’s energy comes as rays which can penetrate the earth’s atmosphere. When hydrocarbons are burnt, their chemical energy is converted into heat (and light) energy which essentially cannot penetrate through the earth’s atmosphere and thus escape.
The earth’s surface become hotter and … the ICE MELTS.
Thanks for the nice A&Q. It is helpful.
No! NOT 100 thousand years of captured energy; 100 MILLION years of captured energy instead. Little wonder the ice melts … and fossil fuel producers, and burners, tell us the warming is NOT because of human activity. How humans can lie!
The glaciers supply around 800 million people with water for irrigation, hydropower and drinking. They will not face difficulties in many areas of life and economy including agriculture. with more water 8bn tons and increasing every year they will have more water. Over the next 50 years the whole world needs to control birth rates.
Please, check the logic — more water and no difficulties.
There’ll be sudden flood, unpredictable flood, over-flow, and then, less and least water, irregular flow of less water.
Does agriculture depend on irregular flow of water?
“Over the next 50 years the whole world needs to control birth rates.”
There are many things that humans need to do, if they are to survive. Most important is to control their own greed. Principally, because of greed, they are destroying the conditions for life on earth. They are polluting the land, oceans, and atmosphere on which all living things depend in so many different ways including monoculture, nuclear radiation, plastics, products from the burning of fossil fuels, etc., and know not how to stop. Greed drives them on. They are tampering with the very foundations of life – the living genomes – and they know not what they do. They are insatiable. Their greed, like their hubris, is boundless. They are the cancer of the earth that seeks to spread to other worlds, such is their greed.