Home / Feature / Global warming is likely to be the greatest cause of climate change

Global warming is likely to be the greatest cause of climate change


Rayhan Ahmed Topader:


The science is clear. Climate change is real. Climate change is happening now. Climate change requires immediate and ambitious action to prevent the worst effects it can have on people and wildlife all over the world.We know that the planet has warmed by an average of nearly 1°C in the past century. If we are to prevent the worst effects of climate change, there is global agreement that temperature rises need to be kept well below 2°C from the pre-industrial era, with an ambition to keep it below 1.5°C. Currently, however, assessments suggest that we are currently on course for temperature rises of up to as much as 4°C or higher.With so many experts on climate change here at Imperial, many people ask them what they personally can do about it? And how does this fit into the bigger picture? They spoke to scientists at the Grantham Institute and drew up a list of the most achievable ways you personally can make a difference. While individuals alone may not be able to make drastic emissions cuts that limit climate change to acceptable levels, personal action is essential to raise the importance of issues to policymakers and businesses.Using your voice as a consumer, a customer, a member of the electorate and an active citizen, will lead to changes on a much grander scale.A prosperous future for the United Kingdom depends on their decisions about the environment, green spaces, roads, cycling infrastructure, waste and recycling, air quality and energy efficient homes.Ultimately, steps to reduce carbon emissions will have a positive impact on other local issues, like improving air quality and public health, creating jobs and reducing inequality. The world is almost out of time with respect to decarbonizing the energy sector. =

Doing so, experts agree, is essential to forestalling some of the most alarming consequences of climate change, including rising sea levels, droughts, fires, extreme weather events, ocean acidification, and the like. These threats have helped generate fresh interest in the potential for nuclear power and, more specifically, innovative nuclear reactor designs-to allow people to rely less on carbon-spewing electricity sources such as coal, natural gas, and oil. In recent years, advanced nuclear designs have been the focus of intensive interest and support from both private investors such as Bill Gates who founded TerraPower, a nuclear reactor design company, in 2006-and national governments, including that of the United States.Advocates hope that this renewed focus on nuclear energy will yield technological progress and lower costs. But when it comes to averting the imminent effects of climate change, even the cutting edge of nuclear technology will prove to be too little, too late. Put simply, given the economic trends in existing plants and those under construction, nuclear power cannot positively impact climate change in the next ten years or more. Given the long lead times to develop.The geoengineering juggernaut has shifted into higher gear with the release of a long-awaited report from the National Research Council recommending federal funding for research into plan B technologies to intervene in the climate system to counter the effects of warming.Reports commissioned by the council are often the trigger for large-scale research programs into new areas of science. Although providing a comprehensive review of the science behind various schemes, the new report is at its weakest when it grapples with the politics of geoengineering. Adopting the line that more research is always a good thing, council scientists do not concede experiments that do not change the physical environment can sharply change the social and political environment.

And so the report treats as only of theoretical concern the possibility that a major research program on climate modification would reduce political incentives to reduce carbon emissions. Anyone who has watched world leaders seize on carbon capture and storage as a means of having our cake and eating it can see what is likely. The world lost 10 years chasing the chimera of clean coal. Questions of control are at the center of the geoengineering debate, especially with respect to the proposal that receives most attention shielding Earth with an atmospheric layer of sulfate particles to reflect some of the sun’s heat. Renamed albedo modification in the council report, it raises many questions. Among them: Can we control the climate system? Can we control ourselves? After all, in full knowledge of the consequences we have failed to reduce greenhouse gas emissions not so much because we do not buy green electricity or switch to public transport but because we cannot stop ourselves voting for politicians whom we know will do little or nothing.Technofixes technical solutions to social problems are appealing when we are unwilling to change ourselves and our social institutions. So here is the essential problem that the council scientists do not confront: Does anyone really believe that while warming is suppressed with a sulfate aerosol shield a revolution will occur in our attitudes and political systems? No.Yet every scientist, including the council authors, is convinced that if albedo modification is implemented and not followed by a program of global emission reductions, then we are almost certainly finished. Sulfate spraying without a change in the political system would make the situation worse.There is a long history of technological interventions entrenching the behaviours that created the problem.

In Navigating Environmental Attitudes Thomas Heberlein tells the story of the New Deal dams of the 1920s and 1930s built to limit severe damage from floods and droughts. Yet flood losses after the dams were built increased. People looked at the now “safe” flood plains and built more houses on them. They were sitting ducks when the rivers once again flooded. The course of a river is easier to shift than people’s attitudes.The council argues that the United States should have a better research base on albedo modification to inform its response should some other actor decide unilaterally to begin spraying sulfates into the stratosphere.

The risk of the National Research Council report is that its warnings about the environmental risks and uncertainties will be overlooked by political players looking for an answer but unwilling to embrace the need it stressed to cut greenhouse gas emissions. Already, politicians loathe to implement serious measures to cut emissions are privately attracted to the geoengineering technofix, including albedo modification, as a substitute.For the moment the political taboo on speaking of it publicly is holding. (Nobel laureate Paul Crutzen broke the scientific taboo with a famous essay in 2006.) But by normalizing geoengineering as one response among a “portfolio” of actions, the council report, backed by the prestige of the National Academy of Sciences, may loosen the prohibition’s grip.A fleet of planes daily delivering sulfate particles into the upper atmosphere would be a grim monument to the ultimate failure of unbridled techno-industrialism and our unwillingness to change the way we live.While we cannot stop global warming overnight, or even over the next several decades, we can slow the rate and limit the amount of global warming by reducing human emissions of heat-trapping gases and soot (black carbon).

If all human emissions of heat-trapping gases were to stop today, Earth’s temperature would continue to rise for a few decades as ocean currents bring excess heat stored in the deep ocean back to the surface. Once this excess heat radiated out to space, Earth’s temperature would stabilize. Experts think the additional warming from this “hidden” heat are unlikely to exceed 0.9° Fahrenheit (0.5°Celsius). With no further human influence, natural processes would begin to slowly remove the excess carbon dioxide from the atmosphere, and global temperatures would gradually begin to decline.Transitioning to energy sources that do not emit greenhouse gases, such as solar, wind, biofuels, and nuclear, can slow the pace of climate change, though these energy sources face hurdles ranging from manufacturing capacity to debates about where to install some facilities. Images courtesy Energy.gov.Alternative methods to slow or reduce global warming have been proposed that are, collectively, known as climate engineering or geoengineering. Some geoengineering proposals involve cooling Earth’s surface by injecting reflective particles into the upper atmosphere to scatter and reflect sunlight back to space. Other proposals involve seeding the oceans with iron to stimulate large-scale phytoplankton blooms, thereby drawing down carbon dioxide out of the atmosphere through photosynthesis. Such methods could work, in principle, but many climate scientists oppose undertaking geoengineering until we have a much better understanding of the possible side effects. Additionally, there are unresolved legal and ethical issues surrounding geoengineering.

In May, the concentration of carbon dioxide in the atmosphere crept up to about 418 parts per million. It was the highest ever recorded in human history and likely higher than at any point in the last three million years.That record was broken in the midst of the coronavirus pandemic, even though the health crisis has driven one of the largest, most dramatic drops in CO2 emissions ever recorded. Meanwhile, ordinary people have blocked tankers and fracking rigs, letting everyone know that renewable energy is the answer to fossil fuels. Indigenous Peoples are most severely affected by both the causes and effects of climate change. They are often on the front lines, facing down deforestation or kicking out fossil fuel industries that want to put their water supplies at risk from oil spills. Communities in the Pacific Islands are facing sea level rises and more extreme weather. But they are using their strength and resilience to demand world leaders take quicker climate action in global meetings, such as COP21 in Paris 2015. For many of these communities, climate change is a fight for life itself. And for many countries around the world, including the UK, climate change is having more and more of a negative impact on people. As a country with the wealth and power to really tackle climate change, it’s never been more important to demand that our leaders act.

Writer and Columnist