Humanity faces significant threats not only from wars, famines, and epidemics but also from actions stemming from human activities. As industrialization rates increase, emitting pollutants into the atmosphere without concern for environmental preservation, we all confront a major challenge: the rise in the Earth’s average temperature, a phenomenon known as global warming. This leads to severe consequences such as ice melting at the poles, rising sea levels that erode land areas, and intense climatic disturbances like storms and hurricanes, unprecedented in Earth’s history. These dangers necessitate raising awareness about the nature of this issue and the urgent need for global cooperation to address it.
The world began to understand the phenomenon of global warming in 1824 when French scientist Joseph Fourier stated that the Earth would be cooler without its atmosphere. Naturally, global warming helps maintain our planet’s climate, making it livable; without it, the Earth’s surface would be about 33°C colder. Seventy years later, Swedish scientist Svante Arrhenius, who later won the Nobel Prize in Chemistry, presented research in 1895 stating that certain gases, notably carbon dioxide, can trap heat near the Earth’s surface, and changes in these gases could significantly impact the amount of trapped heat. The National Oceanic and Atmospheric Administration (NOAA) confirmed this, noting that from 1880 to 1980, global temperatures increased by 0.07°C per decade, accelerating to 0.18°C per decade after 1981, resulting in a current increase of about 2°C compared to pre-industrial times. As of now, 2016 was the hottest year ever recorded, but fortunately, subsequent years have shown a noticeable decrease, with hopes that this trend will continue.
Explaining Global Warming and Its Causes
The primary cause of this phenomenon is the burning of fossil fuels such as coal and oil during industrial processes, which releases gases like carbon dioxide (CO2), the most common, along with water vapor, methane (CH4), ozone, and nitrous oxide (N2O). These gases enter the Earth’s atmosphere, interacting with solar radiation that hits the Earth’s surface and then rebounds as heat. Due to the presence of these gases in the atmosphere, only light passes through while trapping and retaining the heat, preventing it from escaping into space and thus warming the planet.
In addition to industrial emissions, deforestation for agricultural or residential use increases atmospheric CO2 levels. According to the Food and Agriculture Organization, when trees die, they release the carbon stored during photosynthesis. Moreover, the reduction in forest cover decreases carbon absorption from the atmosphere.
Despite being the second most common greenhouse gas, methane is more effective at trapping heat, with the Environmental Protection Agency reporting that methane traps heat 25 times more efficiently than CO2. This gas comes from natural sources, but human activities like mining, natural gas use, landfills, and livestock farming significantly contribute to its emissions, with animals producing about 26% of total methane emissions.
Natural factors like volcanic eruptions, changes in solar radiation due to sunspots, solar winds, and the Earth’s position relative to the sun also contribute to global warming, but their effects are limited compared to human-induced factors.
Effects of Global Warming
Global warming not only causes increased temperatures but also leads to other effects that may result in adverse weather phenomena, such as severe snowstorms. Therefore, researchers and policymakers prefer the term “climate change” in discussions. The effects of global warming are extensive and often devastating, including:
Melting Ice
The most apparent effect of global warming is the reduction of ice cover. North America, Europe, and Asia have seen a decline in snow cover from 1960 to 2015. According to the National Snow and Ice Data Center, permafrost in the Northern Hemisphere has decreased by 10% since the early 20th century. Melting permafrost can lead to landslides and ice collapses, causing significant loss of life and releasing long-buried microbes, as occurred in 2016 with the anthrax outbreak from reindeer carcasses. A 2016 study found a 99% probability that global warming has recently accelerated glacier retreat by 10 to 15 times compared to pre-warming conditions. For example, Glacier National Park in Montana had 150 glaciers in the late 19th century, but by 2015, only 26 remained.
In the Arctic, global warming seems to be progressing faster than at mid-latitudes, with Arctic sea ice reaching record lows in 2015 and 2016. Some scientists predict that the Arctic Ocean may be ice-free in summer within 20 to 30 years if current trends continue.
In the Antarctic, the effects are more variable. Scientists report that a quarter of the ice in West Antarctica is at risk of collapse, with massive glaciers in Thwaites and Pine Island flowing five times faster than in 1992. East Antarctica remains more resilient, but recent data suggests even this cold stronghold is beginning to be affected by rising temperatures, with glaciers moving faster and contributing to rising sea levels.
Drought
Global warming is expected to exacerbate dryness in already arid regions. For instance, the southwestern and central plains of the United States are anticipated to face severe droughts due to increased evaporation from warmer soils and reduced rainfall. Research from 2014 indicates that many subtropical regions will likely experience decreased rainfall due to rising temperatures, including the Mediterranean, Amazon, Central America, and Indonesia, with South Africa, Mexico, Western Australia, and California also facing severe droughts.
Drought poses risks of devastating wildfires, with the National Fire Prevention Center reporting a steady increase in wildfire occurrences compared to the 1980s.
Extreme Weather
Extreme weather is another consequence of global warming, with increased cyclone intensity expected due to warmer oceans, which drive increased humidity, the primary engine of these storms. The Intergovernmental Panel on Climate Change (IPCC) states that even with diversified energy sources and reduced reliance on fossil fuels, tropical cyclone intensity could increase by up to 11%, leading to more damage from these storms along coastlines. As greenhouse gas concentrations remain high, these changes are likely to continue for decades or more.
Ironically, climate change may also increase severe snowstorms. According to the National Environmental Information Centers, severe snowstorms in the eastern U.S. have doubled in frequency since the early 20th century due to increased moisture in the atmosphere from warmer oceans. Additionally, lightning strikes have increased by 12% for every one-degree rise in atmospheric temperatures.
Rising Sea Levels and Ocean Disruptions
Overall, melting ice contributes to rising sea levels. A 2021 World Meteorological Organization report noted that the rate of sea level rise doubled from 2.1 mm per year between 1993 and 2002 to 4.4 mm between 2013 and 2021. It is expected that melting ice from the Arctic and Antarctic, as well as glaciers worldwide, will significantly raise sea levels, accelerating in the coming years and flooding many coastal areas where nearly half of the world’s population resides.
Beyond rising sea levels, immediate effects of global warming include ocean acidification, where dissolved CO2 decreases ocean pH, harming marine ecosystems. This increased acidity erodes calcium carbonate shells and skeletons of marine organisms such as shellfish, crustaceans, and corals. Coral bleaching events, like those in the Great Barrier Reef in 2016 and 2017, have highlighted these risks, making coral survival less likely with repeated bleaching.
Disruptions in Plant and Animal Life
Global warming’s impact on Earth’s ecosystems is profound, with many plant and animal species shifting northward or to higher elevations due to rising temperatures. According to the National Academy of Sciences, many species are migrating from the equator towards the poles to find suitable living conditions. However, the pace of climate change may outstrip the ability of many species to migrate, potentially leading to extinction. Studies suggest that one in three plant and animal species could face extinction by 2070 due to climate changes.
Rising temperatures also expand the range of many pathogens previously confined to tropical and subtropical areas, threatening previously protected plant and animal species.
Social Impacts
The anticipated effects of climate change on human societies could be even more devastating. Agricultural systems are likely to face severe challenges from drought, extreme weather, increased pests, and declining groundwater levels, leading to crop failures, livestock losses, food insecurity, and chaos in global food markets, potentially resulting in famines, riots, political instability, and civil unrest worldwide.
Additionally, global warming poses significant risks to human health. The American Medical Association reports increased mosquito-borne diseases such as malaria and chronic diseases like asthma due to global warming. The 2016 Zika virus outbreak, which causes severe birth defects, highlighted the risks of climate change creating new habitats for disease-spreading mosquitoes. Longer, hotter summers also contribute to the spread of tick-borne diseases.
Addressing Global Warming
Since the 19th century, researchers have improved understanding of the atmosphere and global climate systems. Concerns about global warming emerged in the mid-20th century, prompting scientists to urge governments, manufacturers, and citizens to take steps to reduce greenhouse gas emissions worldwide, especially in industrialized and densely populated countries. North America and Europe were the primary contributors to these emissions since the mid-18th century industrial revolution. Today, large developing countries like China and India have joined, exacerbating the issue and prompting serious efforts to address it through two main policies: “mitigation,” focusing on reducing greenhouse gas emissions by shifting to alternative energy sources like wind, solar, and hydro power, and “adaptation,” aimed at improving societal resilience to changing climate conditions, such as modifying agricultural practices and designing new coastal city infrastructure to handle rising sea levels.
Efforts by many countries to combat global warming include:
Intergovernmental Panel on Climate Change (IPCC)
The first IPCC assessment report, issued in 1990, concluded that human activity is responsible for increasing atmospheric greenhouse gases and that this warming could lead to significant impacts on the climate. The 2014 report confirmed that warming is unprecedented and caused by human activities. The 2021 report states that human activities have already increased global temperatures by 1.1°C, with significant impacts expected in the coming decades even with reduced greenhouse gas emissions.
Paris Agreement
The 2015 Paris Agreement, adopted by nearly 200 countries, aims to limit global temperature rise to well below 2°C, with efforts to restrict it to 1.5°C. This agreement represents a significant step in international cooperation against global warming. In the 2021 COP26 summit, governments agreed to increase climate action efforts, including pledges to reduce emissions and transition to renewable energy sources.
Key Takeaways
Global warming is a complex and multifaceted issue with significant and potentially devastating impacts on the environment, ecosystems, and human societies. While understanding and addressing these challenges is crucial, ongoing research, international cooperation, and concerted efforts are necessary to mitigate and adapt to the effects of climate change. Efforts to reduce greenhouse gas emissions, transition to cleaner energy sources, and enhance resilience to climate impacts remain central to addressing this global challenge.
