Saturday, 22 December 2012

Will we collapse like Easter Island?

The spectacular statues of Easter Island, a sparsely populated Pacific isle which is seemingly so desolate that there are not even any large trees on it, have been a mystery for centuries. How could an island of a few thousand people produce hundreds of such statues, the largest of which are 33 feet tall and weigh 82 tons? This question inspired Erich Von Daniken, a best-selling author of the 1970s, to speculate that the statues were erected by aliens from outer space. The real story of the statues and the people who carved them are the subject of the first chapter of Jared Diamond's book, 'Collapse: How Societies Choose To Fail Or Survive' (published by Penguin in 2006). Diamond is professor of Geography at the University of California at Los Angeles and author of several award-winning books on the impact of the physical world on human history. His Easter Island history turns out to have profound environmental lessons for us even today.
Diamond points out that archaeologists have proved that Easter Island was once very different from today; before being colonised by people, it was covered with forest typical of other sub-tropical Pacific islands. Once settled by explorers who arrived by canoe from other islands, it seemed to present itself as a hospitable place, and the human population expanded rapidly. Incidentally, this solves the mystery of the statues; a population several times bigger could more reasonably be expected to erect such monuments. However, unknown to the new settlers, the soil of Easter Island was much less fertile than that of other islands that they had lived on. This infertility manifested itself in slower tree growth. Thus when the Easter Islanders cut down trees for firewood, houses and deep-sea canoes, they did this at a rate which may have been sustainable on other islands that their ancestors had lived on; but on Easter Island it brought disaster.
As the population grew, people cut down more trees for firewood and canoes. Canoes were necessary as dolphin-hunting provided a large portion of the animal protein in the diet (along with wild birds and other small animals from the forest). But once the forest cover was removed, the exposed land eroded quickly in the rain and wind. Crop yields decreased, and the islanders' solution was apparently to cut down more trees to plant more crops and build more canoes for dolphin-hunting. As a result, within a few centuries the island was completely deforested. Without trees, there were no more wild birds or animals to hunt, except rats. With no more wood available for canoes, dolphin meat was also no longer available. The islanders descended into famine, war and cannibalism (unfortunately, human meat was one of few remaining sources of animal protein). Two-thirds of the population perished in this terrible manner.
Diamond describes other societies that collapsed primarily due to environmental difficulties, including several more Pacific islands, the Norse colony in Greenland, the native Anasazi culture of the southwestern US, the central American Maya civilisation and modern Rwanda. He also presents the case of Japan, which came close to such a fate but managed to avoid it thanks to intelligent decisions and good leadership.
There is a lesson for us here: in these times of global warming, it may be comforting to believe that our leaders can be trusted to sort everything out, and that humanity would never allow itself to be destroyed. But such a faith would be unfounded; many previous societies have thought this way, and failed. Long-term survival requires a real understanding of the limitations of our environment and a strong political will to live within those limits.
Like the first settlers of Easter Island, we find ourselves in a new, unknown environment; namely an industrialised 21st century world with greenhouse gas levels higher than they have ever been in human history. We no longer need to colonise a new island to experience unfamiliar environmental conditions; our carbon dioxide emissions are altering the climate of our whole planet, which will bring unpredictable new risks for everyone. The lesson of Easter Island should make us think on the failure of our own leaders to come to an agreement to prevent catastrophic climate change even after 20 years of fruitless negotiations.
 Copyright 2012 by Zeeshan Hasan. First published in Bangladesh on 22nd December 2012 in the Financial Express.

Saturday, 1 December 2012

How the fossil fuel industry deceives us and endangers our future

For the past 15 years a largely invisible struggle, critical to the future of the planet, has been fought between the global community of climate scientists on one hand and the think-tanks and politicians funded by fossil fuel companies, on the other. During this time, climate scientists have reached an overwhelming scientific consensus that the carbon dioxide emissions caused by our reliance on coal, oil and gas have already caused significant global warming, and will ultimately endanger our planet unless all fossil fuels are rapidly phased out. Simultaneously, the fossil fuel industry has run a huge misinformation campaign to keep the public in the dark about climate change. Ground-breaking scientist Michael Mann writes about this struggle in his new book, The hockey stick and the climate wars; dispatches from the front lines (published 2012 by Columbia University Press).
The critical study which solidified scientific opinion about the truth of global warming was the "hockey stick graph" discovered by author Michael Mann himself in 1998, and highlighted in Al Gore's documentary on global warming, An Inconvenient Truth. Mann's graph showed global average temperatures slowly decreasing towards a distant new ice age for most of the past 1000 years, only to spike sharply upwards in the 20th century (like the end of a hockey stick). The 'hockey stick graph' showed that man-made global warming was real, and was already happening. The 'hockey stick graph' was confirmed by many subsequent scientific studies; the handful of studies which contradicted it were found to have critical errors. Among climate scientists, there was no longer any doubt about the reality and seriousness of global warming.
The fossil-fuel industry, composed of multinational coal and oil companies, sought to protect their business interests by sowing public doubt in global warming, and was quick to strike back at climate scientists. They funded think-tanks and web-sites propagating reports by their own "experts" who cast doubts on the 'hockey stick'. These experts were usually economists and meteorologists/TV weathermen who knew little of climate science, as well as an ever-shrinking minority of climate scientists. The misinformation campaign took advantage of a public and media largely ignorant of science, and unable to appreciate that the real scientific debate on climate change was over. US Congressmen in the thrall of oil and coal lobbyists undertook an official witch-hunt of climate scientists in 2005. The US Congress was, however, unable to find any problems with the climate scientists' views; but the damage was done. Widespread media coverage of politicians like Senator James Inhofe saying that climate change was "the single greatest hoax ever perpetrated on the American public" ensured that doubts about global warming continued in the public mind. The anti-climate science campaign ultimately descended to criminal acts of hacking and baseless accusations of fraud directed at Mann and his fellow scientists. In the 'Climate-gate' incident in 2009, unknown hackers stole thousands of e-mail messages from the Climate Research Unit of the University of East Anglia in the UK. One particular e-mail from another climate scientist to Mann was repeatedly used as evidence to claim that Mann had used a "trick" to falsify his 'hockey stick' data and was thus able to "hide the decline" in global temperature.
Climate change denialists had a field day. In actual fact, the word "trick" is commonly used among mathematicians and scientists to describe a clever means of solving a difficult problem, seemingly by magic; it did not imply any wrongdoing. Likewise, the "decline" in that was being hidden was a series of temperature measurements from one particular study acknowledged by the original author to be doubtful due to pollution. A number of subsequent inquiries were conducted, and none found any wrongdoing on the part of climate scientists. Again, the damage was already done; public belief in global warming and political will to tackle it both fell dramatically.
The fog of public doubt created over global warming had long-term consequences. Firstly, President Barack Obama's attempts at regulating carbon emissions were rejected by the US Congress. Secondly, the 'Climate-gate' hacking had been timed to occur just before the Copenhagen summit on global warming in December 2009. Due to doubts raised by the 'Climate-gate' as well as Obama's failure to pass any carbon dioxide emissions legislation in the US, Copenhagen failed to produce any meaningful international agreement to prevent global warming. This failure has left the planet in continued peril of global warming and consequent sea level rise, cyclones and drought. Hurricane Sandy, US/Russian crop failures and high food prices in 2012 are the beginnings of what is in store for us unless the public and politicians start taking real action to replace fossil fuels with nuclear, solar and wind power.
First published on November 30th, 2012 by the Financial Express in Bangladesh. Copyright 2012 by Zeeshan Hasan.

Sunday, 7 October 2012

Global warming and mass extinction of life on Earth

By Zeeshan Hasan

Climate change is usually thought of as a threat in terms of rising sea levels and increased drought; but science has revealed that it bears further threats. These previously unknown dangers of climate change are the focus of Peter D. Ward's book, "Under a Green Sky: Global warming, the mass extinctions of the past, and what they can tell us about our future" (published 2006 by Harper Collins). Ward is a professor of biology and earth and space sciences at the University of Washington at Seattle, and also works at Nasa. He is one of the biologists whose analysis of the fossil record has helped scientists understand what caused the numerous mass extinctions that have occurred during the history of life on earth.

The most famous of earlier mass extinctions was the one which wiped out the dinosaurs; thirty years ago, scientists confirmed it was the result of an asteroid hitting the earth. Following that great discovery, scientists for years assumed that all the other mass extinctions were similarly the result of asteroid impacts. However, geologists were ultimately unable to find any evidence for those supposed asteroids. Apparently, the extinction of the dinosaurs was unique, and a different explanation was necessary for the remaining mass extinctions. This was ultimately found to be global warming due to excess carbon dioxide in the atmosphere. It turns out that large quantities of carbon dioxide can be released by volcanic activity; this is especially likely in major tectonic events such as when the Indian subcontinent collided with Eurasia (creating the Himalayas).
Ward's book investigates the mechanism by which global warming caused mass extinctions such as the end-Permian extinction event, which destroyed 95% of life on earth 250 million years ago. Scientists have found that most mass extinctions were marked by huge amounts of hydrogen sulphide, which is the smelly, poisonous gas released by rotten eggs. The hydrogen sulphide was created by an oxygen-free "Canfield ocean" (named after the scientist who discovered it), a condition similar to that which now exists in the Black Sea. Canfield oceans occur when global warming melts too much polar ice, releasing so much cold water that the normal ocean currents which circulate water from deep to shallow and keep the oceans oxygen-rich are disrupted. Once this happens, the oxygen-breathing fish and other sea creatures quickly consume all the oxygen left in the water and then suffocate. The remaining oxygen-free water can sustain only anaerobic purple bacteria which require no oxygen to live; by filling up the ocean, these bacteria would also turn the ocean purple.

Anaerobic purple bacteria in a Canfield ocean produce massive quantities of hydrogen sulphide gas, which then bubbles to the surface and poisons animals on land. Hydrogen sulphide also damages the ozone layer, exposing the remaining animals and plants to deadly levels of ultraviolet rays from the sun (as a minor side effect, hydrogen sulphide from a Canfield ocean would also turn the sky green; hence the title of the book). Thus global warming has caused mass extinctions on both land and sea which can only be described as apocalyptic.

How far away is this? We don't know exactly how much polar ice has to melt to create a Canfield ocean and another mass extinction, but we do know the following:
Using [current carbon dioxide emission] rates, which work out to about 120 parts per million per century, we might expect carbon dioxide levels to hit 500 to 600 parts per million by the year 2100. That would be the same carbon dioxide levels that were most recently present sometime in the past 40 million years -- or more relevant, it would be equivalent to times when there was little or no ice even at the poles. (Pages 164-5)

In other words, by the year 2100, within two or three generations, carbon dioxide levels will be high enough to virtually ensure another polar melt. This will likely set into motion a Canfield ocean and mass extinction which humanity may not survive.

Our only chance to avoid this apocalyptic future is to stop using fossil fuels like coal, petroleum and gas, and replace them completely within a few decades with nuclear, wind and solar. This is the only way to prevent further polar ice melting and a Canfield ocean-created mass extinction. Unfortunately politicians and the public are in a state of scientific ignorance and denial of climate change. Anyone who cares about the survival of humanity beyond the next century needs to try to remedy that.

First published in Bangladesh in the Daily Star on 7th October, 2012.

Monday, 14 May 2012

60-90% chance of Bangladesh sinking under rising sea levels

This article was published in the Financial Express in Bangladesh.

“Science as a Contact Sport; inside the battle to save Earth's climate” by Stephen Schneider is an illuminating book by a world renowned climate scientist and professor at the Woods Institute for the Environment at Stanford University. In 2007, Schneider received the Nobel Peace Price on behalf of the International Panel for Climate Change (IPCC), along with Al Gore. His book is a recounting of his efforts over three decades to get the US government and the rest of the world to pay attention to climate change science.

The basic question which climate science has tried to answer is: how serious is climate change? But communicating a scientific answer to this question has been impossible, Schneider says, as politicians, journalists and the average person on the street does not understand that scientific predictions and models of climate change can only predict probabilities of particular outcomes. Unfortunately, the public and the politicians have shown little desire to understand the significance of these scientific probabilities. Instead, they are generally interested in climate science only the extent that it supports their own pre-conceived political beliefs that climate change is insignificant.

If the above sounds familiar, a particular example for which Schneider presents some numbers should frighten all of us. For low-lying countries like Bangladesh, one of the critical questions of climate change is how high sea level rise will be. The answer to this actually depends on whether or not the Greenland ice cap melts; this event would release enough water to raise global sea levels about 25 metres (about 80 feet). This would be the end for Bangladesh, sinking perhaps 75% of the country. It would also be the end of most of the world’s coastal cities like New York, Los Angeles, Washington DC and London. Here are Schneider’s estimates of how likely this is:

For Greenland to irreversibly melt, my own [estimate] would be roughly a 2 to 5 percent chance that it is already too late and it will happen over the long run. At 1 degree Celsius more warming, I’d raise the odds to 25 percent..." (page 274)

So this is the problem of climate science in a nutshell; the likelihood of a major catastrophe like 25 meter sea level rise could be theoretically be as low as 2 to 5 percent. So in the US, Republican politicians like George W. Bush as well as numerous Democrats whose political campaigns rely on donations from oil and coal companies will always focus on the 2 percent probability and dismiss climate change a waste of time. However, for those of us who have not been paid off and can think for ourselves, the rest of the sentence should be shocking:

"...and at 2 degrees Celsius to 60 percent, at 3 degrees Celsius to 90 percent, and so on.” (page 274 continued).

Critically, the basis for all international climate negotiations is to limit global warming to 2 degrees Celsius (as most governments in the world have already decided that it would be too expensive to do anything more than that). This international consensus means that 2 degrees of warming is inevitable, as everyone has accepted that it will happen and will not even try to prevent it. Given that fact, Schneider’s odds for a 25 metre sea level rise and the destruction of Bangladesh becomes 60% to 90% (the 90% figure is still relevant, as it is always possible for countries to fail to cut carbon dioxide emissions enough to limit global warming to 2 degrees).

What to do now? The only people who care about Bangladesh and have the capacity to change anything are Bangladeshis living in Western countries. If they really care about Bangladesh, they should all become climate activists and pressure their governments to do something to prevent this. People in Bangladesh have only two options; firstly, invest vastly more in education and hope people can emigrate before the country sinks. Secondly, invest vastly more in birth control, targeting a 22nd century population of only the 25 million people, which would be the maximum number that the country could support if it was reduced to pockets of high land in Rajshahi division and Chittagong Hill Tracts. Unfortunately, Professor Schneider died from cancer in 2010, and now there is one fewer climate scientist to tell us how we can save ourselves from catastrophic global warming.