Disasters - natural and man-made, Environmental, International, Technical

Building a sustainable society in the age of climate change

In an article published in this website May 15, 2020, I discussed the future of our planet within the context of frontier ethics. The main conclusion was that frontier ethics, which affects our attitudes about the seriousness of environmental problems, will eventually lead to massive resource depletion and ecological disasters, and accelerate the pernicious effects of climate change.

Those who believe in frontier ethics are least concerned about the declining fossil fuel reserves because they are convinced that reserves will never become dry. Their mantra—”Why be efficient if resources are unlimited”—prevents them from using available resources more efficiently. Instead, they maintain that we should increase the search for new reserves, even if it takes us into one of the few remaining pristine wilderness on our planet.

A classic example of someone who preaches and practices frontier ethics is Donald Trump. After becoming president of the United States of America, he signed an executive order opening up the entire coastal plain of the Arctic National Wildlife Refuge in Alaska to oil and gas exploration. Until then, it was an environmentally sensitive area long closed to drilling. Furthermore, he gave the coal industry in America a carté blanche to dig wherever there may be signs of coal. He also repealed former president Obama’s Clean Power Plan, giving states more flexibility to keep coal-fired power plants open.

Arguably, societies that believe in frontier ethics are low-synergy societies treading on a path of unsustainability. In contrast, high-synergy societies live in harmony with nature and they seek ways to enhance natural systems. Creating a high-synergy society that lives within the Earth’s means is possible if we adopt a set of sustainable ethics that ensures future generations and other species the resources they need to survive.

The tenets of sustainable ethics are: The Earth has a limited supply of resources, and they are not all for us; humans are a part of nature, subject to its laws; and success stems from efforts to cooperate with the forces of nature. Clearly, sustainable ethics recognises our place in the natural order as one of many millions of species and they favour cooperation over domination. Also, they are diametrically opposed to the tenets of frontier ethics. While frontier ethics leads to exploitive behaviour, sustainable ethics will lead to a less exploitive human presence that can endure for thousands of years.

In addition to the three tenets, there are at least six principles that lie at the core of sustainability. They are conservation, recycling, using renewable resources, restoration, population control and adaptability. Among other measures discussed below, if we follow these principles, we can create and maintain a well-functioning global ecosystem.

In order to build a sustainable society in which future generations and other species can survive and live well, we have to change our thinking process too—from linear to system thinking. Linear thinking sees events in a straight-line sequence, ignoring a complex web of interactions, while system thinking recognises how entire systems function. In the environmental arena, system thinking helps us to see how individual parts work together and how interdependent all life forms are. By becoming better system thinkers, we can learn to avoid impacts that threaten the health and wellbeing of the planet and its organisms.

Because system thinking encourages us to look at the whole, it will naturally force us to look at the root cause of problems, especially environmental ones. Additionally, it can help society to identify key leverage points as to where changes can be made. Moreover, system thinking will enhance our ability to see the big picture as well as connections between various parts that are essential to solving the many environmental problems, particularly those caused by climate change, and putting us on a sustainable path. Unfortunately, most of the world leaders are not system thinkers and therefore cannot guide us toward a sustainable society.

Building a sustainable society requires widespread participation with input from the rich and poor, conservative and liberal, young and old. In fact, sustainable solutions call for action from large and small businesses, individuals and governments. Individuals are important because each one of us is part of the problem. In other words, seemingly insignificant actions by us, albeit small, are responsible for many environmental problems we are facing today.

Achieving a sustainable world also requires massive cooperation between citizens and governments. Cooperation must occur on a much grander scale, with countries working together for the common good of their citizens and the planet. At the same time, we have to develop a unified strategy to fight the unique challenges posed by climate change.

But how do we achieve this cooperation and develop a unified strategy in an era when climate change is an impediment towards sustainable development? Since 1995, world governments have met every year at the so-called Conference of Parties to forge a global response to the climate change emergency. However, besides stating lofty goals, these dysfunctional conferences were either fractious or soporific. Interspersed with moments of rare triumph though, such as the Paris agreement in 2015, they mostly failed to deliver strong commitments to tackle the terror unleashed by climate change.

In the meantime, the impact of climate change on humans, animals and the environment are becoming increasingly unbearable. It is dragging millions of people into grinding poverty. That being the case, virtually no one any longer believes that these conferences will ever be able to tackle climate change, thereby allowing us to lead a sustainable life. If it sounds downbeat, that is because it is.

So how do we create a sustainable future? As noted by Einstein, “In the midst of every crisis, lies great opportunity.” Indeed, from the current crisis caused by the coronavirus pandemic, we can observe some encouraging trends in our behaviour and lifestyle that have profound implications in the fight against climate change. If we can hold on to these trends in the post-pandemic world, we will be able to face the ongoing existential threat of climate change effectively and thus create a sustainable society.

Quamrul Haider is a Professor of Physics at Fordham University, New York.

Advanced science, Disasters - natural and man-made, Environmental, International, Life as it is, Technical

Coronavirus pandemic – opening the eyes

Human beings had been fighting against the nature, against other animals and even against other human beings for centuries; in fact, ever since human consciousness arose. In doing so, the prevailing science and technology and natural defence were the main armoury of human beings. But now this little virus called Covid-19, so little that it is invisible even to the microscopes, has brought home to human beings in no uncertain terms that human existence is at the mercy of this virus or any similar strain of virus or mutated viruses.

What is this insidious virus that has brought virtually the whole world to a standstill, that is banging the heads of ardent capitalists, committed communists, socialists, devoted Muslims, Christians, Jews, Hindus, Buddhists, mullahs, ayatollahs, rabbis, priests, atheists, agnostics and all other strands of human dogmas come together to fight against it? Political, social, economic, religious divisions are now totally irrelevant against this virus. This virus does not distinguish or differentiate between the prime ministers, presidents, princes, ministers, millionaires, billionaires and destitute, paupers, street beggars etc. This virus can strike anybody at any time and that’s why it is a pandemic now.

This coronavirus is a virus – a miniscule biological entity, a microscopic parasite – that can infect living organisms. The coronavirus is a collective name for a group of viruses that covers everything from common cold to Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). The covid-19 is a particular strain of coronavirus which had popped out, or one can say evolved, only a few months ago (in late 2019) in the wholesale fish market in the city of Wuhan, China. However, Covid-19 strain is somewhat different, more aggressive and contagious than SARS or MERS. Even Covid-19 has a number of strands

This Covid-19 is a variant of SARS that can go from human to human in aerosol form and through body contacts. Although some virologists speculate that it may have jumped from animals or reptiles to humans through food chain, there is no definitive evidence to support this hypothesis. Few days ago, there had been a report that some animals in the zoo in Bronx, New York had developed coronavirus symptoms, probably due to infection from zoo-keepers. This means that this virus or some variation of this virus has the ability to jump back and forth between men and animals.

The virus consists of a nucleic acid molecule (typically RNA or even DNA) with a protein coating to protect itself and distinctive spikes at the outer surface to anchor into a particular type of human cells. As it is a virus, it hasn’t got the ability to replicate itself and multiply. Nevertheless, it does want to survive, as all genes do, by multiplying and moving from body to body to improve its chances to live. To survive and replicate, it needs to find a host cell where it can make use of host cell’s genetic material and protective coating and then it strangulates the host cell so that the host cell cannot hit back and the host cell gradually withers away and dies. This virus when multiplied many times within the safety of a host cell bursts open and spreads out and each one of them then attacks surrounding cells and the process proliferates.

The victory by the virus following the first attack is by no means a smooth affair; it’s a bloody war. When the parasitic virus attacks the body, the immune system of the body (which is a system of proteins and cells that are distributed throughout the body) responds to the invasion. These proteins include antibodies, which lock on to the bits of the virus such as the spike ‘S’ protein. It was this spike ‘S’ protein that was used by the virus in the first place to home in to the body cell and go through the cell membrane. Now this very spike is used by the defence mechanism of the body to identify and target the virus.

Thus, the immune system tries very hard to exterminate the invading virus. A life and death struggle ensue; the virus (Covid-19) knows that unless it can colonise the host cell, it will die and the host cell also knows that if the invading virus wins, it will suck life out of it and the cell will die.

Thus, the immune system tries very hard to exterminate the invading virus. A life and death struggle ensue; the virus (Covid-19) knows that unless it can colonise the host cell, it will die and the host cell also knows that if the invading virus wins, it will suck life out of it and the cell will die.

As this struggle continues, the host body – the survival machine – is blissfully unaware of what is going at the cellular level. There is no outward symptom, no discernible ill effects. It is called the asymptomatic condition meaning no symptoms. After a few days, if the body immune system wins, the invading viruses are crushed and disposed of. On the other hand, if the invading viruses start winning and keep attacking cells after cells, alarm bell starts ringing and messages go out throughout the body that it is under attack. The organs which are lost or partially lost start showing up symptoms. These are sore throat, headaches, persistent coughing as respiratory tract cells gradually become dysfunctional and high body temperature. There may be reduced functionality of other body organs. For example, there may be loss of appetite, aches and pains, dizziness etc.

The body nonetheless keeps fighting. If the invading army of viruses attack and destroy lung cells, which in turn affect alveoli sacs, breathing becomes difficult and artificial breathing using oxygen masks and, in extreme cases, ventilation units may be required to supply oxygen to the body. All is not lost even at this stage and the body can recover. It is anticipated that at least another week or so would be required to recover. However, if there are pre-existing health conditions wherein the immune system was weakened already, such as pre-existing diabetes, heart conditions, kidney problems etc., then the chances of recovery become that much difficult.

Once the viral attack has been successfully overcome, the cells of the immune system would ‘remember’ the virus and its characteristic make-up and any future attack by this virus would be immediately repelled. However, this immune system memory would not last for very long period. Normally two to three years is the maximum for this memory.

To counter this virus, a vaccine is needed to be developed. The vaccine is likely to be a harmless subcomponent of the virus, and the idea is that the vaccine would stimulate the immune system, to develop antibody by lymphocytes and get the body well prepared in anticipation of viral attack.

The presumption among the political and economic leaders of the world is that once the immediate Covid-19 pandemic is overcome and the fatality figure is brought down to nil, everything can be scaled down and life will turn normal again. The reality is likely to be far from this situation. When fatality is brought down to zero in an area or in a country, it does not mean the virus is finished; it is just contained away from human beings. It can come back at any time, despite some precautionary measures.

The graph above shows that a physical system – an earthquake, a disease, a pandemic and so on – may appear multiple times, albeit in damped condition, after the first incidence. The first peak may be much bigger than the second peak, but the second and subsequent peaks cannot be ruled out. Moreover, the time gap between the peaks would depend on the measures taken to terminate such occurrences. The Spanish Flu of 1918 is a case for pandemic example; it came back and ravaged the world number of times over a number of years. So, every precaution must be taken to counter such recurrence.

Admittedly this pandemic is causing untold misery and pain to millions or billions of people round the world. The economy of each and every country is suffering and will bear unimaginable strain due to this pandemic. The social structure is irrevocably strained: social gatherings, public performances, national and international sports and games would be severely curtailed, if not completely abandoned. The education system is at doldrum. In fact, everything that the present civilisation pursues has to be reconsidered.

But much of it, if not all of it, is due to our unbridled activities, as if there is no tomorrow. The Earth had been poisoned endlessly with greenhouse gases (CO2, NOx, CFC etc) leading to unprecedented global warming – the devastating impacts of global warming are yet to come, the Earth and the seas are endlessly exploited, the population is going up and up and within 20 to 30 years it is likely to be over 12 billion. The worst thing is that there is no recognition that we are destroying this planet.

Take, for example, the actions of Donald Trump, the president of the most powerful and flamboyant nation on Earth. He has withdrawn America from the Paris Agreement of 2016 (UN Framework Convention on Climate Change) meaning that he can pursue whatever he wants to do regardless of what happens to Earth’s climate. Only about a month ago, he was dismissive of coronavirus as a common flu and asked people to have common flu precaution. Now, when thousands of Americans are dying in all major cities every day in America, he is blaming the States for not taking measures in time!

Political leaders must understand that short term measures to boost their public rating are causing long term damage to the Earth and the livelihood of common people who live on it. The leaders must be made to bear the consequences of their actions.  World order needs to be rearranged and made favourable to the Earth. Otherwise, the existence of humanity will be at stake.

Dr A Rahman is an author and a columnist    

Bangladesh, Disasters - natural and man-made, Economic, Environmental, International, Life as it is, Political

Abnormal of the past becomes normal of the future in climate change age

Sandbag embankment in Khulna, Bangladesh after the cyclone, Fani in 2019

For millions of years, we were in equilibrium with our environment. Over the past 11,500 years, a period in Earth’s history called the Holocene Epoch, there had been a global climatic stability with the average surface temperature fluctuating around one degree Celsius up or down. Our civilisation emerged and progressed against this backdrop of a relatively stable climate.

Melting glaciers

But then something happened that led to the change of whole edifice for worse. The Industrial Revolution that began around 1760 had drastically changed, indeed corrupted, our environment. Today, we live on a planet whose air is polluted, whose water is contaminated and whose soil is chemically altered. Indeed, human influence is so substantial that Earth is no longer in the Holocene Epoch, but rather in a new geologic epoch, the Anthropocene. For comparison, the epoch before Holocene, the Pleistocene Epoch, lasted nearly 2.5 million years.

Our insatiable appetite for energy using fossil fuel to have higher and higher living standards is placing unbearable burden on the planet. Until 1970s there had been little or no concern about the detrimental effects of extraction and use of fossil fuels on an industrial scale, particularly the amount of greenhouse gases that are released into the atmosphere.  The current concentration of carbon dioxide, the main greenhouse gas in the atmosphere, is about 415 parts per million. It is the highest concentration since the Pliocene Epoch, which extended from about 5.3 million to 2.5 million years ago.

We now live in a world where “abnormal” of yester-years have become “normal” of present day. Examples of present day normal that were abnormal some 50 years ago are Bombogenesis, Arctic Amplification, Hell Fire, Pyro-cumulonimbus Storms aka Fire Tornadoes, Heat Waves and Climate Refugees, Derecho, Sneaker Wave, Squall Line, Microburst, Frankenstorm, and so forth.

Under normal conditions, cold air mass sits above the poles in an area called the polar vortex. It is a large, low-pressure zone that exists at two levels of the atmosphere, one in the troposphere, where most of the weather-related phenomena occur, and the other a bit higher up, in the stratosphere, home of the ozone layer that protects us from the harmful effects of ultraviolet radiation. The vortices are seasonal atmospheric phenomena.

However, scientists believe that the phenomenon of Arctic Amplification, which is the self-reinforcing process that warms the Arctic and subarctic regions much faster than rest of the world, distorts the vortex in the North Pole, thereby resulting in a sudden plunge in temperature south of the Arctic Circle. This anomaly, a consequence of global warming, was abnormal before the 1970s, but quite normal today.

It is no longer implausible to have record snowfall and record high temperature on the same day. On November 16 of last year, Anchorage in Alaska saw its high temperature top out at plus seven degrees at 2:30 a.m. (Average November temperature in Anchorage is negative five degrees.) Before midnight that day, 21 centimetres of snow fell on the ground. This oddity, as well as 20-25 degrees swing in daytime temperature within 24 hours in the winter months—abnormal few decades ago—are normal now.

Located a few feet below the soil surface in extremely cold regions, permafrost is one of the most unique kinds of soil containing more carbon and methane than any other soil on Earth and twice as much carbon as is available in the atmosphere. But as global temperatures rise, Arctic permafrost thaws and greenhouse gases trapped in ice are released. Clearly, permafrost thawing is opening up additional pathways for greenhouse gases, constituting a newly identified, powerful feedback to global warming. Besides, ancient carcasses are emerging from the melting permafrost, and with them germs from illness long thought eradicated.

Nowadays, Australia and California are ground zero for out-of-control wildfires. As cataclysmic wildfires continue to rage across Australia, the loss of life—humans and animals—has reached staggering numbers. An estimated one billion animals have been killed so far and approximately 107,000 square kilometres—roughly 70 percent the size of Bangladesh—burned on the east coast.

Climate change is making heat waves longer and more frequent. Temperatures soaring over 50 degrees in many parts of the world are becoming the norm, while nice and comfortable weather has become the exception.

Some other wild weather phenomena due to climate change that were rare or considered abnormal in the past but not anymore are Derecho—a straight-line wind storm with hurricane-force winds; Sneaker Wave—a disproportionately large wave that suddenly appears during a wave sequence; Squall Line—a line of thunderstorms preceding a cold front; Microburst—severe downdraft caused by a thunderstorm; Frankenstorm—remnants of a super storm reinvigorated by an early winter storm and a blast of Arctic air.

Rising temperatures due to climate change is driving out oxygen from our oceans, threatening many species of aquatic life. According to the International Union of Conservation of Nature, around 700 ocean sites are now suffering from low oxygen, compared with 45 in the 1960s. Lest we forget, oceans are the source of most of the oxygen we breathe.

If the seas ever do rise by even a meter, our children and grandchildren may find themselves living cramped lives with other climate refugees on shrinking continents. “Humorously speaking,” they may even try to adopt the underwater lifestyle of the cartoon character SpongeBob SquarePants, provided ocean acidification caused by absorption of carbon dioxide has not already wiped him and his pineapple home from the bottom of the rising seas.

Few years ago, the sight of polar bears roaming the streets of a village or town would have been abnormal. Nowadays, it is normal because the land on which they live and hunt is under siege. As Arctic ice thins from melting, an occurrence linked to global warming, their habitat is shrinking and food supply is decreasing. As a result, they are moving out of their natural habitat and traveling hundreds of miles south of the Arctic region in search for food.

To tackle these and other new normals, every year since 1995, our leaders and/or their disciples have been meeting at various world capitals or cities, some of which are tourist hot spots―Bali, Cancun, Marrakech, Montreal, Paris―debating climate change in climate-controlled halls at the so-called Conference of Parties (COP). In order to feel what it is like living in one of the hottest places on Earth, maybe they should hold a future COP in halls without air conditioners in Jacobabad (Pakistan) during July when the average daytime temperature regularly surpasses 50 degrees.

The hype around these conferences is high, but expectations of the people are low because the proposals are not bold enough and interests of the developing countries are marginalised. Gone is the focus on establishing global “top down” approach for stabilising emissions of greenhouse gases that would be legally binding. On the contrary, focus is on voluntary “bottom up” commitments by individual nations to reduce emissions.

It has become clear that the much-touted Paris Agreement thrashed out at COP-21 for keeping the rise in global temperature this century to two degrees above pre-industrial levels and to pursue efforts to limit the temperature increase even lower to 1.5 degrees is on life-support system. America under Donald Trump has withdrawn from the Paris Agreement as Donald Trump categorises global warming as “fake news!” Subsequent summits, including COP-25 in Madrid two months ago, were stuck in a rut. There is no agreement yet and none is in sight.

The UN Secretary-General António Guterres roped in some world leaders, members of civil societies and corporate executives at a climate summit in New York on September 23, 2019 to highlight their plans to bring down greenhouse gas emissions to zero by 2050. As expected, they “prioritised” a laundry list of Action Portfolios without any firm commitment to implement them.

The star of the summit was Greta Thunberg, the 17-year old Swedish activist, who delivered a blunt speech, excoriating world leaders for their inaction. And the shameless world leaders clapped and cheered every time she chastised them with phrases like “How dare you,” or “You have stolen my dreams and my childhood with your empty words.” If they had any self-respect, they should have hung their head down in shame instead of applauding. They did not do so because they are “normal” 21st century leaders.

All said and done, what is the end game? Can pre-emptively embarking on a revolutionary change that will lead us away from dependency on fossil fuels and embracing eco-friendly renewable energies save our planet? Can we avoid the risk of a catastrophic failure of our increasingly ephemeral and tightly interlinked global civilisation as we know it? The answer to the above questions is NO, because our leaders lack the collective will to take the decisive steps required to keep our planet liveable for the future generations.

Scientists believe that if we started to cut down on emissions of carbon dioxide even by one percent in 1990, tackling climate change would have been manageable. Instead, we wasted 30 years by inaction. The inertia of the climate system is such that even if we stop introducing greenhouse gases into the atmosphere right now, the ones already in the atmosphere will keep on warming the Earth for another one to two hundred years before equilibrium is reached. In other words, climate change would keep on accelerating, regardless of what measures we take to mitigate its effects.

We can, however, partially solve the seemingly unsolvable problems we have created by changing the unsustainable lifestyle of many of us. More importantly, we have to work to address the problem of the world’s ever-growing population. We are probably within a few decades of a point in time where the sheer number of people on Earth will make continuing degradation of our planet irreversible. So, it is up to us whether we choose to take actions in a direction which will reduce overall global population.

Quamrul Haider is a Professor of Physics at Fordham University, New York.

Advanced science, Environmental, International, Technical

Solar radiation management can help combat climate change

In the Environmental Physics course that I teach from time to time, a student once remarked that we really do not have to worry about the deleterious effects of climate change because technology would be able to solve all the problems we are facing. At that time, I thought this viewpoint is an extreme case of technological optimism. But today, as the likelihood of international consensus to stabilise atmospheric composition of greenhouse gases seems remote while the consequences of climate change are becoming more apparent and direr, many in the scientific community believe that the potential last-ditch effort to stave off the disastrous impacts of climate change is to appeal to technology, geoengineering in particular. Even the United Nation’s Intergovernmental Panel on Climate Change considers geoengineering as a necessary Plan B if global warming does not show any signs of slowing.

Geoengineering is deliberate, large-scale manipulation of the Earth’s environment to counteract anthropogenic climate change. It encompasses two different approaches using a variety of cutting-edge technologies to undo the effects of greenhouse gas emissions. They are removal and sequestration of carbon dioxide to lower its concentration in the atmosphere and offsetting global warming by targeting the overall amount of solar energy reaching the Earth. The removal technologies were discussed in an op-ed piece published in this newspaper on November 29, 2018.

Some of the offsetting options scientists are exploring are reflecting part of the sunlight back into space before it reaches the Earth’s surface, allowing more of the heat trapped by the Earth’s surface to escape into space, and increasing the reflectivity of roofs, Arctic ice, glaciers, pavements, croplands and deserts. Known as Solar Radiation Management (SRM), these options would slow down the rise in Earth’s temperature until carbon dioxide emissions can be reduced enough to prevent catastrophic repercussions of human-driven climate change.

The fraction of incoming sunlight that is reflected back to space could readily be changed by increasing the reflectivity of the low-level clouds. This could be achieved by spraying seawater in the air where they would evaporate to form sea salt, which would seed the clouds above the oceans making them thicker and more reflective. Several simulations have confirmed that the seeding mechanism, also known as Marine Cloud Brightening, would work with the likelihood to lower temperatures at a regional level.

Another proposed cloud-based approach involves thinning the high-altitude Cirrus clouds in the stratosphere by injecting ice nuclei into regions where the clouds are formed. These wispy clouds do not reflect much solar radiation back into space, and instead trap heat in the atmosphere by absorbing thermal radiation emitted by the Earth. While this method is not technically an example of SRM, thinning Cirrus clouds would provide more pathways for the trapped heat to escape into space, and thus, potentially cool the Earth. Currently, work in this field is limited to theoretical studies at research institutions. However, research shows that a cooling of about one degree Celsius is possible by thinning the clouds globally.

Scientists have known for a long time that volcanic eruptions could alter a planet’s climate for months on end, as millions of sunlight-reflecting minute particles (aerosols) are spread throughout the atmosphere. Indeed, the “cold and miserable” summer of 1816 in China, Europe and North America is attributed to the enormous eruption of the Indonesian volcano Tambora in 1815. Though the aerosol haze produced by the Tambora eruption reflected less than one percent of sunlight, it was enough to drop global temperatures by as much as two degrees by the summer of 1816.

The 1991 explosion of Mount Pinatubo in the Philippines cooled the Earth by about 0.5 degrees, while the average global temperatures were as much as one degree cooler for the next five years after the 1883 eruption of Krakatoa in Indonesia. Furthermore, the volcanic-induced cooling of the oceans caused by Krakatoa’s eruption was enough to offset rise in the ocean temperature and sea level for a few decades.

Inspired by these eruptions and the subsequent cooling effect of their sunlight-blocking plume of sulphate particles, scientists are suggesting injecting sulphate aerosols or hydrogen sulphide in the stratosphere. The geoengineering research programme at Harvard University is currently trying to model how clouds of such particles would behave.

One of the more practical SRM techniques that can be implemented easily is whitening surfaces like roofs, croplands and pavements to reflect more sunlight back into space. By absorbing less sunlight, they would negate some of the warming effect from greenhouse gas emissions. This is what greenhouse owners do with whitewash and blinds.

The small island of Bermuda in the North Atlantic is leading the way with white roof houses that not only reflect sunlight, but also keep the homes cooler during the hotter months. A study at the Lawrence Berkeley National Laboratory in California indicates that a 1,000 square foot of white rooftop has about the same one-time impact on global warming as reducing ten tons of carbon dioxide emissions.

Ice sheets are responsible for reflecting lots of sunlight into space. So less ice in the Arctic due to melting means less heat leaving the planet. Hence, scientists want to spread tiny glass beads around the Arctic in the hopes of making the polar ice more reflective and less prone to melting. Another idea is to cover deserts and glaciers with reflective sheets.

Perhaps the most challenging concept to control solar radiation entails deploying an array of reflecting mirrors at strategic points between the Sun and the Earth—just as we all do with sunscreens and sunblocks. Calculations by space scientists at the Lawrence Livermore National Laboratory in California indicate that a mirror roughly the size of Greenland would be able to block one to two percent of solar radiation from reaching the Earth. The idea of a sunscreen is still on the drawing board.

Finally, as we transition into a new era in which human activity is shaping the Earth more than the natural forces, technology could be seen as a way of humans reshaping the planet by limiting the adverse effects of climate change. Also, because international political efforts to curtail greenhouse gas emissions have been slow in coming, solar radiation management is a possible measure to be used if climate change trends become disruptive enough to warrant extreme and risky measures.

Quamrul Haider is a professor of physics at Fordham University, New York.

Advanced science, Bangladesh, Environmental, International, Life as it is, Political, Technical

We are hurtling towards a disastrous Climate Change (Part II)

In Part I, it was shown unambiguously that human activities from the period of industrial revolution (1720 – 1800) had been the root cause for the rise of global temperature by over 1ºC due to emission of greenhouse gases into the atmosphere. As industrial activities became more and more widespread, the greenhouse gas emission and its accumulation in atmosphere increased correspondingly and the global temperature went up even higher.

Climatologists, Geoscientists, Atmospheric Scientists and so forth had been warning the world leaders of signs of increase in global temperature over and above the natural increase right from the early 1970s. As time passed, their warning became louder and louder, but the leaders of industrialised countries deliberately ignored them or rejected their scientific evidence. United States of America is, in particular, the champion of such denial right from the beginning – presidents like Ronald Reagan, George H W Bush, George W Bush and recently Donald Trump are all rejectionists of man-made global climate change.

Despite incontrovertible scientific principle and evidence that increase in carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbon (CFC) and other gases in atmosphere traps energy i.e. heat within earth’s atmosphere and thereby increase global temperature, the deniers reject all these arguments. Their short-sightedness and the damage they are inflicting on Earth are simply inexcusable.

The consequences of global increase in temperature are given below:

When air temperature increases, land surface temperature increases more than the sea temperature, as heat capacity of water is more than that of soil. What it means is that for the same amount of heat, water temperature will increase less (due to its high heat absorbing capacity) than that of soil. Similarly, when air temperature drops, land temperature drop would be more than sea temperature. Thus, sea temperature does not move up or down as much as the adjoining land mass temperature and that is why we get the moderating effect of sea.

This land-sea temperature differential is also the cause of rain, storm, snowfall etc. In the summer, land temperature increases substantially causing air to rise to high altitude and sea air being relatively cooler and heavier but laden with moisture moves towards land and gives rain. A higher temperature difference would give higher amount of rain, higher wind velocity (storm, tornado etc). Reciprocally, in the winter there would be severe snowfall, extreme cold spell etc. So, the climate change would exacerbate the nascent conditions.   

Melting of inland glaciers around the world, which would then be followed by Antarctic and Greenland ice sheets melting would cause sea-level to rise significantly. It is not only the extra volume of water from melting ice but also the thermal expansion of water due to rise in temperature that would cause sea-levels to rise and inundate large areas of land mass. It is estimated by the Inter-governmental panel on Climate Change (IPCC) that by the end of this century, the sea-level is likely to rise by at least 6ft (or even higher), if no remedial action is taken now i.e. if life continues as ‘business-as-usual’. But if action is taken urgently now to limit temperature rise to 1.50C, the sea-level rise may be contained within 3ft to 6ft.

Figure 1. Mangrove areas of Sundarbans in Bangladesh at present

In addition to that, worsening storm surge, frequent tropical storm and concentrated rainfall will affect large coastal areas and even inlands of a country, islands and low-lying areas. Bangladesh, a low-lying country, would be badly affected by sea-level rise. The average landmass there is only about 5ft above the sea level. Figure 1 shows the mangrove areas of Sundarbans in the southern part of the country at present and Figure 2 when sea level rises by the smallest estimated margin of about 3ft.  It can be seen that large areas have been inundated by the rising sea level. It is estimated that 1.3 billion people world-wide would be affected, which may require their permanent relocation or even mass migration.

Figure 2. Mangrove areas of Sundarbans in Bangladesh anticipated to be around 2050 AD.

It may be pointed out that sea-level rise does not just cause submersion of landmass, which might have been habitable area previously, but also damages arable land. Ingress of saline water precludes cultivation of crops, vegetation etc even in surrounding areas which are not inundated. 

Thawing permafrost speed up global warming, as permafrost is basically soil that stays below freezing (00C) for at least two years. Plants capture carbon dioxide (CO2) from the atmosphere by photosynthesis process and then this carbon is released when wood (in roots) decays in the soil or carbon is compressed in the natural process to form coal. In Arctic areas, wood decay or decomposition is very slow and hence these areas are regarded as carbon sink. However, decomposition increases as temperature increases causing enhanced carbon emission. The inventory of frozen carbon in permafrost is 1.5 trillion tons, which is nearly twice the amount of carbon in the atmosphere now!

Wildfires are caused due to global warming and these then contribute to further global warming. Wildfire thus has a positive (destructive) feedback effect. Trees and vegetation absorb CO2 and convert it to oxygen (O2), thus acting as sinks. Tropical forests in Indonesia, Malaysia, Brazil and in other parts of the world play a vital role in carbon sequestration. However, wildfires effectively convert the sink of carbon straight into source of carbon! The forest fires that are razing in the Amazon rain forest now, which is regarded as the lungs of the planet Earth, are extremely damaging. These forest fires are not natural wildfires; these are deliberate man-made fires to clear forest areas for agricultural use (deforestation). Man is making the planet uninhabitable. 

The effect of all these changes is causing severe disruption to the climate. Where there were moderate rainfalls, now there are severe rainfalls causing flash flood, bursting of dams, landslides etc. In 2018, there were devastating floods in Japan, North Korea and India. In 2019, bridges in North Yorkshire, England collapsed when full month’s rain fell in just four hours.

While some parts of the world were having tremendous amount of rainfall in short spell of time, others were baking in heat waves. France’s capital Paris experienced this summer (June 2019) the highest temperature of 46ºC and India experienced 50ºC. Pakistan experienced a deadly heat wave where highest recorded temperature was 54ºC!

There were unprecedented wildfires in Greece and Australia. Wildfires in the forest area called Paradise in California are devastating and becoming a regular event. Northern Finland (in Arctic Circle) and Siberia were used to be considered so cold that wildfires were thought to be incredible, but not anymore. Last year as well as this year, wildfires in those areas devastated large land mass.

In the year 2017, hurricane Irna, a category 5 storm, was the most powerful Atlantic storm in a decade to strike the Caribbean and Southern US. In addition, hurricane Harvey in Texas and hurricane Maria in Dominican Republic wrought havoc. Monsoon floods in Bangladesh and mudslides in Sierra Leone are devastating natural disasters in 2017.

The frequency and severity of these natural disasters are breaking all previous records. A natural disaster, which only 10 or 15 years ago would have been considered once in 100 years event, is now happening once or twice a decade and if runaway conditions are allowed to continue, those events may become regular events!

Donald Trump not only denies man-made climate change but also encourages activities which cause climate change. He and his right-wing coterie of extremist Republicans in America hold and promote the view that climate change is due to natural phenomenon. There is an Institute in America, called the Heartland Institute (which Trump endorses and supports) which claims to be one of the world’s “leading free market think-tanks” and promotes “free market solutions to social, economic and environmental problems”. It disputes scientific observations and knowledge on climate change (as is usual with right-wing cliques to denigrate scientific knowledge), criticises climate mitigation activities and promotes use of fossil fuels. 

When confronted with increased severity and more frequent incidences of droughts, forest and bush fires, floods, storms, tropical cyclones, cold spells etc, these climate change deniers assert these are just natural phenomena; nothing to do with human activities. Their denial is either based on sheer ignorance or moral depravity.

Dr A Rahman is an author and a columnist