Friday, August 17, 2007
The Urgency of Global Warming
Why we should all worry about global warming?
Global warming will worsen the huge inequalities that already exist, within our society, and globally. We already have a troubling relationship with Nature and recent human activity is changing whatever harmony exists in an unprecedented, and soon, irreversible way.
Some of the things we have always taken for granted, such as the availability of water, and human habitation along the coast, along much of India, is very likely to be impacted severely. As a consequence, we will be able to grow lesser essential foods such as rice and wheat, and millions of people will get displaced from coastal areas. There will be greater deaths and spread of disease due to greater warming. Tens of thousands of other species are expected to become extinct. The extent to which all this will happen depends on the choices we make.
What is global warming?
For millions of years, the Sun’s energy has nourished the Earth, generating and sustaining all plant and animal life on the planet. A large amount of that energy bounces back into space and some of it is captured by the atmosphere, maintaining warmth and natural balance.
That harmony has been unbalanced by human beings. Our consumption of coal, petrol, diesel, etc, and other human activity such as mining, clearing forests for wood, even agriculture, generates carbon dioxide (CO2), methane, and other greenhouse gases. CO2 levels in the atmosphere have gone up from 280 parts per million at the time of the Industrial Revolution to about 380 ppm currently. Other gases emitted raise this figure to an equivalent of 440 ppm. These gases don’t allow the Sun’s heat to escape sufficiently, hence warming the planet, the atmosphere, the land, even the deep oceans. As a consequence, on an average, the Earth is at least 0.76 degrees centigrade (1.4 degrees F) warmer than it was at the time of the Industrial Revolution. Much of this has happened in the last few decades.
0.76 degrees C does not seem like very much …
Already, as a consequence, permafrost – ice that has remained frozen since the last Ice Age – is melting. Droughts in the Horn of Africa are more frequent, affecting the poor there. More intense rainfalls (such as the one that hit Bombay two years ago, in which a thousand people were killed) are getting more common, as are intense cyclones, such as Hurricane Katrina.
Islands are drowning and people losing their land and livelihoods, such as in the Sunderbans as the sea level slowly gets higher and eats away at low-lying lands; Himalayan glaciers, including the source of the river Ganga, are receding. The crazy weather is already there for all to see – floods in Rajasthan, drought in Cherrapunji, snow in Dubai … it’s strange and it’s all related to global warming. It’s been estimated by the World Health Organization (WHO) that 1,50,000 additional people are dying each year from diseases, which spread more widely due to warming.
And 0.76 degrees is only an average. Some areas are warming more. In India for instance it is expected that North India will warm more than other regions. Also, further warming is unavoidable because the gases mentioned above stay in the atmosphere long after they are emitted. Hence the gases we emit now will continue to warm the Earth for generations in the future.
What kinds of human activity cause global warming?
Much of it began with the Industrial Revolution, is closely associated with accelerated use of energy through fossil fuels, and has been much sharper in recent decades. Each year, humans emit over 26 billion tons of CO2, 28% more than we used to in 1990. The chief sources of emissions are electrical power (24%), land use (18%), transport (14%), industry (14%) and agriculture (another 14%). But bear in mind that human & animal intensive agriculture, in countries such as ours, not only provides food but supports the bulk of our populations. It is essential to human existence, cars and planes are not.
Emissions have been growing sharply due to reckless mining, deforestation, wasteful production and consumption of coal and oil. Modern warfare, so dependent upon planes, fuel and minerals, has also been much to blame. Globalization – with its faster and wider movement of goods and people – is a major factor. It has not helped that consumption has become a thing to be proud about. Anyone who can afford it now drives a car, and cars emit a kilo of carbon dioxide every 6 kms. Hence a car-ride say from Delhi University to CP would emit 2 kilos of CO2. Flights are much cheaper than they used to be. More electrical gadgets at home mean more use of power, directly and indirectly. After all, there is a direct link between how much we earn and consume, and global warming.
What impact will be felt in the near future?
Even small degrees of further warming will have huge consequences, on human beings, and also on innumerable other species. Less than 1.5 degrees of warming will affect coral reefs in the Indian Ocean and essential species lower down in the sea food chain. At about 1.5 degrees above pre-industrial levels, yields of wheat, rice and other crops will decline in India, and droughts become much more widespread. The recent summary ‘Climate Change Impacts’ by the Intergovernmental Panel on Climate Change (IPCC) bluntly states that 20-30% of plant and animal species face increased risk of extinction!
The poor get more badly hit. Though all countries are going to get affected in different ways, the poorer tropical countries in Asia and Africa are going to get worst hit. In some African countries, yields from rain-fed agriculture could halve by 2020. And the poor within these countries are less equipped to deal with further stress. Global warming will worsen already existing inequalities between rich and poor as resources, particularly water, get scarcer, and as agriculture becomes more difficult to carry on.
How will it affect people in India?
It is expected that the land that glaciers cover will decrease to one-fifth in some years. This will mean more floods at first and then less water for people as rivers dry. For the first time in history, the Ganga and Brahmaputra are expected to dry up in summer, becoming seasonal rivers. As water sources dry up and ground water falls further, access to water for drinking, for general use and for agriculture will become even more difficult than at present. Crop yields in South Asia, says the IPCC report, “could decline by 30% by mid-century”. Mind you, all this in a country in which agriculture is already in crisis and which has the greatest number of malnutritioned children in the world.
Unseasonal rains and heavy rains (such as the one that hit Mumbai) will become more common, particularly over the western coast. North India will get even warmer, where already hundreds die each year of heat stroke due to malnutrition and poor housing and shelter.
Rising sea levels will affect millions of people along India’s vast coastline. A large chunk of India’s population lives within 50 kilometres of its coastline. Many of them grow crops, which will be hit by storms, floods, rising sea levels and saline water entering groundwater sources. Fishing communities will be hit as will millions who live in cities on the coast. There will be a vast influx into existing spaces. This is a disaster on a massive scale with so many aspects, some signs of which are already visible.
Why is it so urgent to act?
We are not too far away from a critical point at which global warming becomes irreversible. Currently, the land, forests and oceans absorb half our carbon dioxide emissions. As the Earth gets warmer, the capacity of the land and sea to absorb carbon dioxide will reduce – it is already reducing – hence more remains in the atmosphere, warming the Earth further. And as Arctic and Antartic ice melts faster, less heat gets reflected back, warming the oceans and causing further melting.
Second, the Earth itself would start contributing to warming. A vast expanse of ice in Western Siberia is melting, which could release over time 70 billion tons of methane in the soil underneath (methane is 23 times more potent as a warming gas than carbon dioxide). As trees burn or rot due to warming, further carbon dioxide gets released. When soils warm up, microbes in the soil will process them faster, emitting carbon dioxide rather than absorbing it. Essentially, in some years, living systems on Earth will begin to emit more carbon dioxide than they absorb.
That critical point at which global warming becomes irreversible is widely accepted as a 2 degree rise, or just 1.25 degrees C from the present. We will reach that point in about 20-25 years. That might seem like ample time to act, but remember that CO2’s warming effects persist years after it is emitted. Hence to avoid reaching tipping point, we need to not just maintain current levels, we need to ensure drastic cuts in carbon emissions. In short, we have to act with great urgency. Before it is too late.
What is the Indian government’s response?
The Indian government has been saying that US and other first world countries are mainly responsible – here they are right – so they ought to take steps before India does; in this they are wrong. Such a position is shortsighted because it ignores the fact that India will be hugely affected. India ought to take the lead in promoting clean technologies and sources of power such as wind and solar energy and put pressure on other countries to do the same. But to the contrary, the Indian government has been promoting cheap cars, cheap flights, malls and the consumption culture, and is permitting mining in many states, all of which will be disastrous. We simply cannot ignore the fact that the time to act is running out fast.
What can all of us do about it?
We need to do three things: influence government policy framework and choices, struggle for greater equity of all kinds, and reduce consumption to what is absolutely necessary, particularly by the affluent, so that there is room for growth for the under-consumers of today and future generations.
We need to pressurize the Indian government to put more priority on conservation, generate more of its electricity from cleaner sources like wind power and solar power instead of coal, and to promote buses, metros and cycle paths in cities instead of cheap cars.
We also need to consume less in the relatively well-off urban areas. This is not easy because we are all used to certain levels of comfort that rise all the time. Consuming less could mean taking the bus instead of a car or auto, trains instead of cheap flights, making do with less electricity, fewer gadgets and less in general. It does not help to use CFL lights at home, feel nice about it and then take a car to college. All of this is not easy when it is 40 degrees in summer. But bear in mind we have no options left.
Even if you are convinced, one would face a feeling of helplessness: what’s the use of my consuming less if everyone else is carrying on happily driving around and not changing their lifestyle. However, there has been a much greater awareness of global warming in India in recent months and movements for change sometimes start with a few people. Things have been changing even in the US, the worst offender. On 14 April earlier this year, 1,100 groups in numerous cities organized to pressurize the US Congress to tackle global warming.
We also need to push for more sustainable and equitable development, because long-term solutions to global warming can only lie in greater equity. But because of the urgency of the situation, we have to combine all possible strategies, short-term and long-term, individual and collective. Nature as we have known it and the planet itself is at stake. As someone said, it’s the only one we’ve got.
Posted by Delhi Platform at 9:15 PM
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Today's newspaper had three news items, all related to floods due to intense rainfall: deaths from flooding in a coal mine in China; 13 suicides in Vidarbha in the last couple of days due to fields being flooded from rains and 318 deaths so far in Bihar from the ongoing massive floods in North India. Though of course it is not necessary that all floods are caused by global warming, intense flooding is very much linked to GW. And this is only going to intensify and happen again and again. As the UK floods suggest, govts are ill-prepared.
Here are some interesting things to think about.
1. Liquify all the CO2 we put into the air every year. Put the stuff into a container. What would the volume of the cointainer be? The answer is around 30 cubic kilometres. A cube with that volume would be around 3 kilometers long, 3 kilometers wide and 3 kilometers deep (want to avoid the expense of burying it? then worry about the temperature in the air 3 kilometers up).
2. The Blog needs correcting because the sun has been pumping energy into the earth since the birth of the solar system some 4.6 billion (not millions) years ago.
3. The ppm story: the Blog said that we have 440 ppm CO2e (ppm means "parts per million"; CO2e means "as if CO2 was the only GHG")of GHG's in the air right now. Suppose we keep emitting GHG's at the present rate; how would the Co2e ppm value grow? The Stern Report on the Economics of Climate Change says, in its Full Executive Summary, that the figure would go up to 550 ppm by 2050 and keep increasing therafter. It adds that, at that level, there is at least a 77% chance and perhaps upto a 99 % chance depending on the climate model used for doing the calculation, that the global temperature rise would exceed 2 degrees Centigrade.
4. What does "global temp. rise" mean? That all parts of the earth will see the same rise? NO! The simplest way to see what it means is to ask, "Suppose, for some reason, that the temperature around the equator goes up by 1 degree celsius; how much will the Earth's other regions heat up? That they will heat up more is obvious because the earth's climate system, meaning its winds and its ocean curents, are the major parts of a giant machine that redistributes the direct solar energy that the earth gets, from the places where that energy is the most, which is the tropics, to the temperate/polar zones where the direct solar energy is smalller/smallest (the Gulf Stream - I'll say more about it soon - is the most well known part of this massive machine). To cut a long story short, a 1 degree Celsius temperature rise in the Earth's equatorial belt means a 12 degree Celsius rise in temperature at the poles. So, if you hear/read that the Arctic sea ice now breaks up, at its southeren edges, earlier and earlier in the year every year, and that when the ice refreezes, during the Northern hemisphere's winter, every year, it fails to refreeze as much as it used to, that 12 to 1 ratio tells you why.
4. The Gulf Stream: It carries water and energy. How much water and how much energy is transported, in one year, as the thing moves from the Gulf of Mexico to Europe? Lets start with the yearly mass transported. How does it compare with the other things that carry water, like rivers and rain. More mass than the Amazon carries? Yes. How much more? 100 times more (NB: The amazon is the worlds mightiest river; it carries the most water to the ocean; the claim that the Nile is longer than the amazon is disputed in: http://news.bbc.co.uk/1/hi/world/americas/6759291.stm). What about comparing the flow rate in the Gulf Stream to the amount of rain that falls every second over the whole planet; more or less? Neither! Its about equal to it, at 15 million cubic meters per second. The Gulf Stream is so massive then the name Planet Earth needs changing....to Planet Ocean. Think about it. Not satisfied. Well, here is another figure. How much energy does the Gulf Stream carry. What base figure to take for comparison. Lets take the total, yearly incoming solar energy that falls on all of the Earth's surface, the solid part and the water part, north of the 40th parallel. Well, the energy in the Gulf Stream is about one third of that awesome amount of energy.
5. Where does the Gulf Stream go to after Europe?: They didn;'t tell you that in school, and you didn't care to ask. Well, it wanders off to a place called the GIN sea, G for GreeenlaND, i FOR Iceland and N for Norway, adjacent to those 3 places.... and then plunges down, all 100 amazon rivers of it and all 30% of the solar energy of it, to the ocean bottom. Just do a google on "The Great Ocean Conveyor Belt + wikpedia" to see pix of the belt. Then ask yourslef why the Stream goes down...or read the article and find out.
Very interesting comment from Meher Engineer.
I understood the CO2e to mean CO2 equivalent, i.e. it's about 380 ppm carbon dioxide and then if we were to add up the other greenhouse gases (GHGs) - methane, etc -it would add up to roughly 440 CO2e (that seems to be the most common figure, though some literature I've read mentions 450 CO2e).
This 2 degree rise Meher mentions seems very crucial does it not? Monbiot also refers to it, only he says one may get there by 2030, Stern says 2035, but the threats of massive feedbacks around those temperature rises seem very significant though by many accounts some significant feedback - such as soil warming in the UK - seems to have already begun.
I remember reading this interesting news item about a scientific report about the Gulf Stream, about it slowing down over the years, if I remember by about 30 per cent or so. Probably varies over the year depending on the temperature since that is one thing that drives the stream does it not?
It's actually quite alarming that GW has managed to alter something as elemental and huge as rainfall and ocean currents.
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