First and last
Throughout its 4.5 billion-year history, the Earth has experienced significant climate changes, driven by natural forces such as volcanic activity, solar fluctuations, and orbital shifts. Periods like ice ages, interglacial periods, and warming events have shaped the planet’s environment and life forms. However, while natural climate variability is a well-documented part of Earth's history, the recent acceleration in climate change, particularly since the rise of Homo sapiens and, more drastically, the Industrial Revolution, is unprecedented in both speed and intensity. This rapid change, driven by human activity, has caused a marked departure from the natural climate cycles that once dominated the planet, especially in the last decade.
The Earth's climate has always been in flux, shaped by geological and environmental factors that have caused shifts between cold and warm periods over millions of years. For instance, the planet has experienced five major ice ages, with the most recent one starting around 2.6 million years ago and continuing in cycles of glaciation and interglacial warmth. During these ice ages, massive ice sheets covered large portions of the Earth, followed by warming periods that caused the glaciers to retreat and sea levels to rise.
One of the most dramatic climate shifts in Earth's history occurred well before the age of the dinosaurs, during the Permian-Triassic extinction about 252 million years ago. Intense volcanic activity and massive methane releases triggered rapid global warming, resulting in the extinction of nearly 96% of marine species and 70% of terrestrial species. Although these catastrophic changes unfolded over thousands to millions of years, allowing some ecosystems to gradually adapt, the environmental upheaval was so extreme that only a small number of species survived. These survivors later evolved, eventually giving rise to the age of the dinosaurs.
In the aftermath of this extinction, the Triassic Period featured a warm and dry climate that gradually facilitated the recovery of life, including the emergence of early dinosaurs. This relatively stable climate continued into the Jurassic Period, where high levels of carbon dioxide fueled the growth of vast forests and supported the dominance of dinosaurs in a humid, greenhouse-like environment. The following Cretaceous Period was one of the warmest in Earth's history, with tropical conditions extending to the poles and minimal permanent ice. However, volcanic activity and tectonic shifts toward the end of the period contributed to a gradual cooling. This era ended abruptly with the Cretaceous-Paleogene extinction, triggered by an asteroid impact that caused a dramatic cooling and the extinction of the dinosaurs, clearing the way for mammals to rise as the dominant species.
Around 56 million years ago, the Paleocene-Eocene Thermal Maximum marked another rapid warming event, driven by the release of large amounts of carbon dioxide and methane. While this period led to extinctions in the deep sea, it also created favorable conditions for the rise of mammals and early primates. In the subsequent Oligocene epoch, Earth's climate began to cool significantly, leading to the formation of large ice sheets on Antarctica and more temperate, polar climates.
The Pleistocene epoch, starting around 2.6 million years ago, is best known for its repeated ice ages, where massive ice sheets expanded and retreated in cycles, separated by warmer interglacial periods. During this time, human ancestors evolved, adapting to both glacial and interglacial climates. After the last major ice age, the Holocene epoch, beginning about 11,700 years ago, ushered in a relatively stable climate that allowed human civilizations to flourish. During this time, humans began altering the landscape through farming, deforestation, and the gradual use of resources. While these actions had localized environmental impacts, they did not yet significantly affect the global climate.
The tipping point for human-driven climate change came with the advent of the Industrial Revolution in the late 18th century. The widespread burning of fossil fuels—coal, oil, and natural gas—released vast quantities of carbon dioxide and other greenhouse gases into the atmosphere. This marked the beginning of what is now called anthropogenic climate change, as human activities began to have a measurable impact on the Earth’s climate.
Since the Industrial Revolution, the global average temperature has increased by approximately 1.8°F, with the majority of this warming occurring over the last century. This rise in temperature has triggered the melting of polar ice caps, rising sea levels, and an increase in extreme weather events, including more frequent heatwaves, droughts, and hurricanes. The Industrial Revolution, coupled with the expansion of capitalism and a rising global population, not only accelerated the emission of greenhouse gases but also drove widespread deforestation and land-use changes, further intensifying the effects of climate change. These human activities have significantly altered the planet’s natural systems, contributing to the rapid environmental shifts we face today.
The most alarming aspect of this trend is how much it has accelerated in the last few decades. While natural climate changes occurred over millennia, modern human-driven climate change is happening in a matter of decades, leaving ecosystems and species with little time to adapt. The last decade has seen the most rapid and alarming increases in global temperatures, with 2020 tied as one of the hottest years on record. According to NASA and the National Oceanic and Atmospheric Administration (NOAA), every year since 2015 has ranked among the hottest years in recorded history. This unprecedented warming is largely due to the continued rise in greenhouse gas emissions from industrial activity, deforestation, and the burning of fossil fuels for energy, transportation, and agriculture.
One of the clearest indicators of this rapid change is the accelerated melting of polar ice caps and glaciers. The Arctic sea ice is shrinking at an alarming rate, with the summer minimum shrinking by about 13% per decade. The Greenland Ice Sheet, which holds enough ice to raise global sea levels by 23 feet, is losing ice at a faster rate than ever before. This loss of ice not only contributes to rising sea levels but also reduces the planet’s ability to reflect sunlight, leading to further warming in a feedback loop. Additionally, the last decade has seen an increase in extreme weather events, which scientists attribute to climate change. More frequent and intense hurricanes, wildfires, and droughts are becoming the new norm, devastating ecosystems and human communities alike. The wildfires in Australia in 2020 and California in recent years have been some of the most destructive on record, fueled by higher temperatures and prolonged dry conditions. These events are not isolated incidents but part of a larger pattern driven by rising global temperatures.
The rapid pace of change in the last decade is alarming because it demonstrates that the window for mitigating climate change is closing. According to the Intergovernmental Panel on Climate Change (IPCC), we have only a short time left to significantly reduce greenhouse gas emissions if we are to avoid the worst impacts of climate change. The IPCC’s 2018 report warned that global temperatures must be kept within 2.7°F of pre-industrial levels to prevent catastrophic consequences. However, if current trends continue, we are on track to exceed this threshold by 2030.
The widespread use of coal and oil as primary energy sources has been integral to the development of modern civilization. Coal was a key driver of the Industrial Revolution in the 18th and 19th centuries, providing the energy needed to power steam engines, factories, and railways. As industries expanded, coal became the dominant fuel source, replacing wood in many parts of the world due to its higher energy density. Similarly, oil began gaining prominence in the late 19th century, especially with the advent of the automobile and the internal combustion engine. By the 20th century, oil surpassed coal as the dominant global energy source, fueling transportation, industry, and electricity generation.
While coal and oil have been instrumental in economic development and industrialization, they have also come with significant environmental costs. Both fuels are fossil fuels, meaning they are formed from the decomposed remains of ancient plants and organisms, which are burned to release energy. However, this process also releases large quantities of carbon dioxide (CO2) and other greenhouse gases into the atmosphere. Since the Industrial Revolution, the burning of coal and oil has drastically increased the concentration of CO2 in the atmosphere, contributing to the rise in global temperatures and the onset of human-driven climate change.
Coal is one of the most carbon-intensive energy sources. When burned, it releases more CO2 per unit of energy than either oil or natural gas. According to the International Energy Agency (IEA), coal accounts for about 40% of global CO2 emissions from fuel combustion, despite contributing only about 27% of the world's energy. Additionally, coal mining can have a destructive impact on ecosystems, with practices like mountaintop removal causing deforestation, habitat destruction, and water pollution. The continued use of coal in power plants, particularly in developing nations like China and India, remains a significant barrier to reducing global carbon emissions.
Oil, while slightly less carbon-intensive than coal, remains a major contributor to climate change. It is the primary fuel source for the transportation sector, which accounts for about 25% of global energy-related CO2 emissions. The extraction and transportation of oil also come with environmental risks, such as oil spills, which can devastate marine ecosystems. Famous disasters like the Exxon Valdez oil spill in 1989 and the Deepwater Horizon spill in 2010 highlighted the long-term environmental damage caused by the oil industry. Beyond emissions and spills, oil refineries emit pollutants like sulfur dioxide and nitrogen oxides, which contribute to air quality degradation and public health issues.
Transportation, particularly the use of cars, airplanes, and private jets, is one of the leading contributors to climate change due to the burning of fossil fuels. The emissions from transportation account for a significant portion of global greenhouse gases (GHGs), with cars and airplanes being major culprits. According to the Environmental Protection Agency (EPA), the transportation sector accounts for about 29% of U.S. GHG emissions, the largest share of any sector. Globally, it’s estimated that transportation accounts for about 14% of GHG emissions, according to the (IPCC). The environmental impact of transportation has become a central issue in the fight against climate change, with increasing attention on how to reduce the carbon footprint of vehicles, flights, and particularly private air travel.
Cars are a significant source of CO2 emissions, which are produced when gasoline and diesel fuels are burned. The widespread use of personal vehicles, especially in countries like the U.S., China, and parts of Europe, contributes heavily to CO2 emissions. In 2020, light-duty vehicles—primarily cars and small trucks—accounted for about 57% of the total transportation emissions in the United States. On average, a gasoline-powered car emits about 4.6 metric tons of CO2 annually, according to the EPA. This figure is based on an average fuel economy of around 22 miles per gallon and an average of 11,500 miles driven per year.
The environmental impact is exacerbated by the sheer number of cars on the road. There are over 1.4 billion cars in the world today, with that number continuing to grow, particularly in developing countries. Even as fuel efficiency improves and electric vehicles (EVs) grow in popularity, the majority of vehicles still rely on fossil fuels, meaning that they continue to contribute to global warming. Efforts to reduce the impact of cars on the environment include transitioning to electric vehicles and encouraging the use of public transportation, biking, and walking to reduce overall fuel consumption.
Air travel is another major contributor to climate change. While airplanes account for only 2-3% of global CO2 emissions, their environmental impact is disproportionately large due to the altitude at which emissions occur. Airplanes emit carbon dioxide, water vapor, nitrogen oxides, and particulates directly into the upper atmosphere, where these emissions have a greater warming effect compared to emissions at ground level. This makes aviation responsible for about 3.5% of human-caused global warming when accounting for these additional effects, according to a study in Environmental Research Letters.
With air travel becoming more accessible globally, emissions from airplanes are expected to increase sharply in the coming decades. According to the International Air Transport Association (IATA), the number of airline passengers is expected to grow to 8.2 billion by 2037, nearly double the 2017 total. This increase in air travel is likely to exacerbate the sector’s already significant contribution to climate change unless there are dramatic shifts toward more sustainable aviation fuels or technologies.
While commercial aviation contributes significantly to GHG emissions, private jets have a much higher carbon footprint per passenger. Private jets are far less fuel-efficient than commercial airplanes, with a single flight producing 5 to 14 times more emissions per passenger than a commercial flight, according to a report from Transport & Environment. Despite making up a small fraction of the total number of flights globally, private jets account for a disproportionate share of aviation emissions. A 2020 study found that just 1% of the global population is responsible for more than 50% of commercial flight emissions, and private jet owners are a significant part of this group.
For example, a single private jet flight from London to New York can emit as much carbon dioxide as an average person emits in an entire year. Additionally, private jets often fly shorter distances, where emissions per mile are higher because more fuel is burned during takeoff and landing.
Animal agriculture is one of the leading contributors to environmental degradation, significantly impacting the planet through greenhouse gas emissions, deforestation, and excessive water use. This industry, driven by global demand for meat, dairy, and other animal products, plays a critical role in climate change, biodiversity loss, and resource depletion. Livestock production alone is responsible for approximately 14.5% of global greenhouse gas emissions, according to the Food and Agriculture Organization (FAO) of the United Nations. These emissions primarily come from methane produced during digestion by ruminants like cows, sheep, and goats, nitrous oxide released from manure and fertilizers, and carbon dioxide from deforestation and fossil fuel use. Methane is particularly potent, with a global warming potential 25 times greater than carbon dioxide over a 100-year period. In fact, livestock production emits more greenhouse gases than the entire transportation sector.
Deforestation is another major consequence of animal agriculture, particularly in regions like the Amazon rainforest, where vast areas of forest are cleared for cattle ranching and growing feed crops like soy. The World Wildlife Fund (WWF) estimates that 80% of deforestation in the Amazon is linked to cattle ranching. Globally, livestock production occupies around 77% of all agricultural land, despite producing only 18% of the world’s calories. This disproportionate use of land for animal agriculture is highly inefficient compared to plant-based food production, and the resulting deforestation not only destroys critical ecosystems but also eliminates forests that act as carbon sinks, absorbing carbon dioxide from the atmosphere.
Water use is another area where animal agriculture has a significant impact. Producing meat and other animal products requires vast amounts of water, both for the animals themselves and for growing the crops used as feed. The Water Footprint Network estimates that animal agriculture accounts for 29% of the global water footprint of agriculture. For example, producing 1 kilogram of beef requires approximately 15,400 liters of water, while 1 kilogram of chicken requires about 4,300 liters. In comparison, 1 kilogram of vegetables requires only about 322 liters of water. This highlights the inefficiency of meat production in terms of water usage, contributing to water scarcity, especially in regions already facing droughts. Furthermore, the waste generated by livestock operations pollutes water bodies with nitrogen, phosphorus, and pathogens, leading to harmful algal blooms and dead zones, such as the Gulf of Mexico's dead zone, where nutrient runoff from livestock farms has caused widespread devastation to marine life.
While the wealthiest 1% of the global population undeniably bears a disproportionate share of responsibility for carbon emissions, it's crucial to acknowledge that Americans in general contribute significantly to climate change due to their relatively high wealth and consumption patterns. The average American lifestyle is far more carbon-intensive than that of most people worldwide. For example, the average American emits about 16.5 metric tons of CO2 per year, compared to the global average of 4.8 metric tons. This means that even middle-class Americans contribute more to global carbon emissions than most people living in lower-income countries.
One key factor behind this disparity is the high-consumption lifestyle typical in the U.S. Americans own more cars, travel frequently by air, consume more energy for heating and cooling, and purchase goods that require energy-intensive production and shipping. According to the IEA, the U.S. remains one of the largest CO2 emitters globally, largely due to its dependence on fossil fuels for transportation, electricity, and industry.
Transportation is a significant source of emissions for Americans. The average U.S. household owns about two cars, and the majority of daily commutes are done in personal vehicles powered by gasoline or diesel. The EPA estimates that nearly 29% of U.S. greenhouse gas emissions come from transportation, a much higher percentage than in countries where public transit is more prevalent. With car ownership so widespread, personal vehicle use contributes heavily to the overall carbon footprint of the American public.
Air travel is another major contributor to the high carbon footprint of the average American. While private jets are notoriously bad for the environment, even commercial flights produce significant emissions. The average American takes about three flights per year, adding substantially to their carbon footprint. In contrast, much of the global population rarely, if ever, flies. For those in developing countries, air travel is simply not financially accessible, resulting in a much smaller individual carbon footprint.
Additionally, meat consumption in the U.S. plays a considerable role in climate change. Americans eat more meat per capita than almost any other nation, particularly beef, which is highly resource-intensive and carbon-emitting. Livestock farming, especially for beef, contributes around 14.5% of global greenhouse gas emissions, according to the FAO. The production process involves large amounts of land, water, and energy, and emits methane, a potent greenhouse gas. The U.S., as one of the largest meat-consuming nations, shoulders a large share of this environmental burden.
In addition to personal lifestyle choices, the structure of the U.S. economy and its focus on consumer culture exacerbate the country’s carbon footprint. Capitalism encourages continuous consumption of goods—such as electronics, clothing, and luxury items—that require energy-intensive manufacturing, transportation, and disposal. As one of the wealthiest countries, Americans, on average, have the financial power to engage in high levels of consumption, contributing further to environmental degradation.
Beyond personal consumption, wealthy individuals in the U.S. often hold substantial stakes in companies responsible for large-scale pollution. Energy companies, particularly those involved in oil, gas, and coal, contribute disproportionately to carbon emissions. According to the Carbon Majors Report, just 100 companies are responsible for 71% of global industrial emissions since 1988. These companies are often owned or controlled by wealthy investors who continue to profit from unsustainable practices, highlighting the intersection of wealth and environmental harm.
The capitalist system, particularly in the U.S., drives this cycle of wealth accumulation at the expense of environmental sustainability. The pursuit of endless economic growth and short-term profits fuels the extraction and burning of fossil fuels. Corporations and wealthy individuals are incentivized to ignore the long-term environmental costs, allowing them to benefit financially while poorer populations—those least responsible for climate change—suffer the worst impacts, from rising sea levels to extreme weather events. This deepens the moral and environmental injustice at the heart of the climate crisis.
In the past few decades, there has been a significant push from fossil fuel companies and other major corporations to hide or distort climate data for profit. This strategy is part of a broader agenda to protect their financial interests, even as the scientific consensus on climate change has grown stronger. Many of these companies, particularly in the oil and gas sectors, have spent millions of dollars on lobbying efforts and disinformation campaigns to delay or block climate regulations. The result is a system in which short-term corporate profits are prioritized over the long-term health of the planet and its inhabitants.
One of the most infamous examples of this is ExxonMobil, which, as early as the 1970s, had access to internal research indicating that fossil fuel emissions were contributing to climate change. Despite this, the company engaged in a concerted effort to cast doubt on the science of climate change, funding think tanks and public relations campaigns aimed at promoting climate skepticism. According to investigative reports, ExxonMobil spent millions of dollars on misleading campaigns to confuse the public about the reality of global warming and its link to fossil fuels. This effort helped delay regulatory action that could have curtailed emissions and limited the catastrophic impacts of climate change.
These efforts were not confined to the oil and gas industry. Koch Industries, a conglomerate involved in fossil fuel refining and chemical production, has been a major funder of climate denial organizations and lobbyists. According to reports, Koch Industries and its network have poured tens of millions of dollars into opposing climate policies, attacking environmental regulations, and backing politicians who deny or downplay the existence of climate change. The company has funded research groups, advocacy organizations, and political candidates that align with their interests, all in an effort to protect their bottom line and maintain the status quo.
The influence of these companies extends to politicians, many of whom receive campaign contributions from fossil fuel interests in exchange for favorable policies. The influence of money in politics has allowed fossil fuel companies to effectively buy political support, ensuring that efforts to regulate emissions are watered down or blocked altogether. This relationship between industry and politicians is particularly evident in the United States, where fossil fuel companies have spent hundreds of millions of dollars on political donations and lobbying. According to OpenSecrets, a nonprofit that tracks money in politics, the oil and gas industry spent over $125 million on lobbying in 2020 alone, with much of that money going to support politicians who oppose climate action.
This pattern of corporate greed and political influence has exacerbated the climate crisis. By delaying regulatory efforts and fostering a culture of climate denial, these corporations have ensured that global emissions continue to rise, pushing the planet closer to catastrophic tipping points. The pursuit of profit, regardless of the environmental costs, has led to increased reliance on fossil fuels, higher levels of pollution, and greater resistance to transitioning to clean energy sources.
Moreover, the climate disinformation funded by these corporations has had a lasting impact on public opinion. Many people remain skeptical of climate science, even as the evidence becomes overwhelming, largely due to the decades-long campaigns of misinformation. This skepticism has slowed down the public’s willingness to support aggressive climate policies, which in turn provides more cover for politicians and companies to delay meaningful action.
When it comes to individual beliefs and actions regarding climate change, several psychological phenomena and logical fallacies play a significant role in justifying inaction or denial. One of the most prominent psychological phenomena is cognitive dissonance, which occurs when people experience discomfort from holding two conflicting beliefs or actions. For example, someone may understand the reality of climate change but continue engaging in high-carbon activities like driving long distances or frequent air travel. To resolve this discomfort, they might downplay the severity of climate change or rationalize their behavior, rather than making efforts to change it.
Another key phenomenon is confirmation bias, where individuals seek out information that supports their pre-existing views while ignoring or rejecting evidence that contradicts them. In the case of climate change, skeptics often consume media that emphasizes uncertainty or downplays scientific consensus, reinforcing their doubts. This bias makes it harder for individuals to accept the mounting evidence of human-caused climate change. Similarly, optimism bias leads people to believe that negative events—such as the effects of climate change—are more likely to affect others rather than themselves, reducing the perceived urgency of taking action.
Normalcy bias also plays a role, where people tend to underestimate the likelihood and severity of future climate-related disasters, assuming that things will continue as they have in the past. This makes it difficult for individuals to comprehend the magnitude of potential climate crises. Meanwhile, diffusion of responsibility leads individuals to assume that others—whether governments, corporations, or future technological advances—will address the issue, leaving them feeling less personally accountable for taking action on climate change.
On the logical fallacies side, the false dilemma fallacy, or presenting a choice between two extremes, is common in climate discussions. People may argue that addressing climate change means sacrificing economic growth, ignoring the possibility of solutions that balance both environmental protection and economic prosperity. The appeal to nature fallacy is also prevalent, where some individuals claim that climate fluctuations have always occurred naturally, so human-driven climate change isn’t a concern, disregarding scientific data showing that current warming is unprecedented in speed and scale.
Additionally, the slippery slope fallacy is used to argue that even small actions to mitigate climate change, such as regulating emissions, will lead to extreme consequences like economic collapse. This fallacy is often employed to create fear and resist environmental regulations. Ad hominem attacks are another tactic, where climate change deniers attack the credibility of scientists or institutions instead of addressing the evidence itself. Finally, the bandwagon fallacy encourages people to believe that since most individuals aren’t making significant changes, they don’t need to either, failing to recognize that collective action is necessary to combat climate change.
By understanding these psychological mechanisms and logical fallacies, individuals can become more aware of how their reasoning might be flawed or influenced. Overcoming these cognitive barriers is essential for fostering more proactive and responsible responses to the climate crisis.
The unfortunate reality is that meaningful change on climate issues won’t occur until the general American public is sufficiently educated and motivated to act. While poorer countries already bear the brunt of climate change and are keenly aware of its devastating effects, they have limited power to make significant changes. Their voices often go unheard in the global arena, overshadowed by the interests of wealthier nations and corporations. Wealthy individuals and companies, who are disproportionately responsible for emissions, have little incentive to change because their profits are tied to the very systems causing environmental destruction. As long as their wealth continues to grow, there is no immediate financial motivation for them to alter their behaviors or practices.
However, the average American holds significant power when it comes to addressing climate change. The choices they make—such as the brands they support, the politicians they vote for, and the lifestyle changes they adopt—can directly influence the actions of the wealthy and the corporations they control. Large companies are driven by consumer demand, and if the public begins to favor environmentally responsible products and policies, corporations will be forced to adapt to maintain profits. Likewise, elected officials rely on public support, and if voters prioritize climate action, it will become a central issue in policy-making.
Until the American public fully realizes its power to influence change, the wealthy will continue exploiting the planet, as their current trajectory offers little reason to adjust. It’s only when public pressure threatens to affect their financial standing that we’ll see a shift in their behavior. Therefore, widespread education and public engagement are essential to driving the systemic changes needed to combat climate change.
That may very well be why corporations and the wealthy work so hard to confuse the public. For years, industries that profit from practices harmful to the environment—such as fossil fuels, agriculture, and manufacturing—have invested heavily in disinformation campaigns to sow doubt about the realities of climate change. These tactics aim to keep the public confused, misinformed, and disengaged, ensuring that they don’t demand the kind of systemic changes that would disrupt the profit models of these industries.
By promoting climate skepticism, downplaying scientific consensus, and exaggerating the economic costs of addressing climate change, these campaigns make it harder for the average person to grasp the severity of the issue. The more confused the public remains, the less pressure there is on corporations to change their behavior or for governments to enact meaningful legislation. It’s a deliberate strategy to protect their financial interests, knowing that as long as the public is misinformed, their profits remain safe.
Educating oneself on climate change is crucial, but it is equally important to act immediately. The scientific consensus is clear: climate change is accelerating, and delaying action only worsens its effects. Learning about the causes and consequences of climate change empowers individuals to make informed decisions, from voting for climate-conscious policies to reducing personal carbon footprints. However, education alone is not enough—there must be a collective push for immediate action. Every day that passes without significant changes to energy use, deforestation, and industrial emissions brings us closer to irreversible damage. Immediate, large-scale action is needed to prevent catastrophic outcomes, both for the environment and for future generations.
To effectively combat climate change, individuals can make a powerful impact by aligning their actions with sustainability goals. Voting for politicians who hold corporations accountable and champion climate policies—such as renewable energy investments, stricter emissions regulations, and environmental protections—ensures that meaningful, systemic changes occur at a larger scale. Supporting eco-conscious brands that prioritize sustainability and lower carbon footprints pushes the market towards greener practices. Adopting a vegan or plant-based diet significantly reduces the environmental impact of food production, as animal agriculture is a leading contributor to greenhouse gases. Reducing needless consumption, including cutting back on frequent online shopping from platforms like Amazon, helps lower waste and the energy-intensive demands of manufacturing and shipping. Additionally, opting for local vacations and choosing sustainable transportation options instead of airplane travel helps curb the high carbon emissions associated with flying. Together, these mindful lifestyle choices contribute substantially to the global fight against climate change.
