Saving the Planet: Understanding the Science of Climate Change

Saving the Planet: Understanding the Science of Climate Change - A Primer

(Estimated reading time: 13 minutes)

Within the past few decades or even years, extreme weather events are becoming more frequent and severe. Back in 2019, an unprecedented deadly heatwave hit Europe. South Africa, particularly in Cape Town, experienced a severe drought in 2018. Hurricane Harvey hit the Gulf Coast of the United States back in 2017. Drier conditions caused the devastating wildfires that ravaged Australia between 2019 and 2020 and have become frequent threats to many parts of the United States. Europe also experienced extreme flooding in 2021, and strong typhoons continue to ravage many countries in South East Asia.

Are these isolated events? Or, is there one underlying cause that contributes to such extreme conditions that threaten the survival of our planet? Questions such as these can quickly escalate from a genuine effort to seek answers to a heated argument between two opposing opinions. The answers to these questions can vary depending on the sources available and the context they induced. But we can agree that one reliable measure of factuality is when a claim is backed by pieces of evidence, such as data, statistics, research, and observation.

The next paragraphs require an open mind, as most readers are assumed to have different opinions about the topic. Let us begin with what science says and why we should trust it. Science points to one thing that causes such conditions - that is, climate change.

Why trust science

First, let us establish why we should trust science regarding climate change. Science is reliable since it uses empirical evidence and logical reasoning to develop theories or scientific models, tested by observation and experimentation. Scientists rigorously test and evaluate hypotheses to yield accurate and reliable results. It is also transparent and self-correcting, with scientists regularly publishing their findings. Such publications are peer-reviewed, allowing other fellow scientists to critique the work. This ensures that people in the same field of expertise can scrutinize the research so that errors or inaccuracies are identified and corrected over time. Every scientific consensus is based on multiple lines of evidence and comes from different fields of research. Also, much scientific research has led to medical breakthroughs and advances in technology that give solutions to complex problems and improve our understanding of the natural world.

There are many fields of research included in the study of climate. This includes atmospheric sciences, geology, biology, and oceanography. They provided evidence backed by research that leads to the conclusion that the Earth's climate is changing and that the major contributor to that is human activities.

What we mean by climate change

As a definition, climate change refers to the long-term alterations in the Earth's climate patterns, with characterized changes in temperature, precipitation, sea levels, and extreme weather events. The scientific consensus is that climate change is occurring and that human activities primarily cause it, particularly the emission of greenhouse gases such as carbon dioxide (CO2) into the atmosphere.

What greenhouse gases are

Greenhouse gases trap heat in the Earth's atmosphere, contributing to the warming of our planet. The most important greenhouse gases are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), all of which occur naturally in the atmosphere. Although in recent studies, pieces of evidence show that human activities are a significant contributor to the excess of such gases that cause the warming.

Greenhouse gases play a crucial role in regulating the temperature of the Earth's atmosphere and making life on our planet possible. Greenhouse gases are, in fact, beneficial to life on Earth if it has not reached a certain alarming level. Let us cite some of their benefits:

Keeping the planet warm: Greenhouse gases, such as carbon dioxide, methane, and water vapor, trap some of the sun's energy in the atmosphere and prevent it from escaping back into space. This helps to keep the planet warm enough for life to exist. Without the natural greenhouse effect, the Earth's average temperature would be about 0 degrees Fahrenheit (-18 degrees Celsius) (NASA).

Supporting plant growth: Carbon dioxide is also essential for plant growth and photosynthesis. Higher levels of carbon dioxide in the atmosphere can increase plant growth rates and improve crop yields (Columbia Climate School, How Climate Change Will Affect Plants).

Preventing extreme cooling: In addition to preventing extreme heating, greenhouse gases can also prevent extreme cooling. They trap heat in the atmosphere by absorbing energy from the sun that would otherwise be reflected back into space. For example, during the last ice age, which ended about 11,000 years ago, carbon dioxide levels dropped to around 200 parts per million (ppm), which is close to the level at which plant growth would stop (NASA).

However, the problem is that human activities have significantly increased the amount of greenhouse gases in the atmosphere, such as oil and gas production, landfills, and agricultural practices.

Carbon dioxide is released through the burning of fossil fuels, deforestation, and other land-use changes. Methane is produced by processes such as livestock digestion and wetlands. Nitrous oxide is emitted by using nitrogen fertilizers in agriculture and other industrial processes. Such processes lead to an enhancement of the natural greenhouse effect.

The more greenhouse gases there are in the atmosphere, the more heat is trapped, leading to an increase in global temperatures. This has resulted in a warming trend that is unprecedented in human history, with the last four decades being the warmest on record.

The increased temperatures caused by greenhouse gases have several impacts on the environment, including the melting of glaciers and sea ice, rising sea levels, and changes in precipitation patterns. These changes, in turn, have a range of consequences for human societies, including impacts on agriculture, water resources, and public health (IPCC).

What the evidence says

Yearly surface temperature compared to the 20th-century average from 1880–2022. Blue bars indicate cooler-than-average years; red bars show warmer-than-average years. NOAA Climate.gov graph, based on data from the National Centers for Environmental Information. (Source, Climate.gov)

Based on current research, such as those already stated above, climate change is unequivocal and primarily caused by human activities, particularly the burning of fossil fuels such as coal, oil, and gas. This lead to the release of excess carbon dioxide and other greenhouse gases into the atmosphere. Data shows that carbon dioxide levels are increasing due to human activity. Measurements of carbon dioxide in the atmosphere show that concentrations have increased significantly since pre-industrial times, and the isotopic composition of the carbon dioxide indicates that the increase is due to the burning of fossil fuels (IPCC).

Evidence shows that the Earth's average surface temperature has increased by 1.5°C since the late 1880s, with the last six decades being the warmest on record. (IPCC) The temperature rise is consistent with the observed atmospheric concentrations of greenhouse gases which have risen from pre-industrial levels of about 200 parts per million (ppm) to over 400 ppm in 2021. (NASA)

Also, the magnitude of recent warming is unusual. The current rate of warming is much faster than the natural warming and cooling cycles that have occurred in the past. The Earth has experienced many natural climate variations, such as the ice ages and interglacial periods, but these occurred over much longer periods than the current warming trend (NASA).

Related to this, the timing of the observed warming of the Earth's surface matches the timing of the increase in greenhouse gas emissions from human activities, rather than from natural factors (NASA).

Models cannot replicate warming without human influence and natural factors alone cannot account for the observed warming trend. Climate models that attempt to simulate the Earth's climate have been unable to replicate the observed warming without including the effects of human activities. Natural factors such as changes in solar radiation, volcanic activity, and natural variations in the Earth's orbit have been carefully studied. They can affect the Earth's climate but do not explain the observed warming trend, as these factors have not increased enough to explain the observed warming. (IPCC).

The after-effect: rising sea levels

NASA has conducted extensive research on rising sea levels and their causes. According to NASA, sea levels have risen by about 8-9 inches (21-24 centimeters) since 1880, and the rate of sea level rise has increased in recent decades.

Moreso, research shows that the primary cause of sea level rise is the melting of glaciers and ice sheets, particularly in Greenland and Antarctica. As temperatures warm, the ice sheets and glaciers melt and flow into the oceans, causing sea levels to rise.

In addition to ice melt, NASA's research has also shown that thermal expansion, or the expansion of seawater as it warms, contributes to sea level rise (NASA).

The end result: extreme weather conditions

There is evidence to suggest that rising sea levels are linked to an increase in extreme weather conditions. As sea levels rise, coastal flooding becomes more frequent and severe, and storm surges can have a greater impact. This can lead to an increased risk of extreme weather events such as hurricanes, typhoons, and cyclones.

In addition, rising sea levels can also lead to changes in ocean currents and weather patterns, which can affect global weather systems and lead to more frequent and severe weather events.

A study published in Nature Communication in 2017 found that rising sea levels could increase the frequency of extreme coastal flooding events by a factor of 100 or more in some areas, particularly in tropical regions.

Another study published in the Scientific Data in 2015 found that climate change increases the frequency and intensity of extreme weather events, including hurricanes, floods, and heatwaves.

Overall, while the link between rising sea levels and extreme weather conditions is complex and multifaceted, there is growing evidence to suggest that the two are connected.

According to the World Health Organization (WHO), climate change is estimated to cause approximately 150,000 deaths per year worldwide. This includes deaths from extreme weather events such as floods, droughts, and heatwaves, as well as indirect effects such as malnutrition, waterborne diseases, and respiratory illnesses caused by air pollution.

In the United States, the National Oceanic and Atmospheric Administration (NOAA) reports that extreme weather events have caused an average of 341 deaths per year between 1980 and 2023. This includes deaths from hurricanes, floods, tornadoes, and other weather-related disasters.

In Europe, a study published in The Lancet in 2019 estimated that climate change was responsible for approximately 1,500 deaths per year in the European Union between 1981 and 2010. This included deaths from heatwaves, cold spells, and wildfires.

The Global Climate Risk Index 2020, produced by the environmental organization Germanwatch, analyzed the impacts of extreme weather events on countries around the world between 2000 and 2019. The report found that over 495,000 people died as a direct result of more than 12,000 extreme weather events during this period, with developing countries being the most affected. The report also noted that low-income countries are particularly vulnerable to climate change impacts, where reported countries and territories affected most in 2018 were Japan, the Philippines as well as Germany. For the period from 1999 to 2018 Puerto Rico, Myanmar and Haiti rank highest.

It's important to note that these statistics are estimates, and the number of deaths caused by extreme weather events and climate change may be higher or lower depending on the range of factors. However, they do provide a useful indication of the significant impact that climate change can have on public health and safety.

Why do people believe that climate change is just a hoax?

Despite the overwhelming evidence backed by research and observation, many believe climate change and climate science are hoaxes. One must broaden perspective and maintain an objective attitude toward such people to be able to understand them and be able to explain to them why it is critical to shift their perspective:

Lack of knowledge or understanding: Some people may not have the necessary education, training, or scientific literacy to understand the complex system of climate, the way atmospheric chemistry works, or the difference between climate and weather.

Misinformation or propaganda: Some people may be exposed to deliberate or unintentional misinformation, rumors, conspiracies, or mistrust in the media, authority figures, or peer-reviewed science. Some industries, political groups, or lobby groups may also have a vested interest in promoting their own agenda or discrediting scientific evidence that contradicts their goals or beliefs.

Ideology or worldview: Some people may reject the idea of human-caused climate change because it conflicts with their preconceived ideologies, political affiliations, and religious or personal beliefs. Climate change may be perceived as a challenge to free-market capitalism, personal freedoms, or national sovereignty, leading some individuals to reject it unconsciously or consciously.

Fear or anxiety: Climate change may be a source of anxiety, guilt, or despair for individuals who may feel powerless, overwhelmed, or conflicted about their role in contributing to the problem or their ability to be part of the solution. Denying or dismissing climate change may be a way to alleviate these negative emotions.

Why climate change is not a hoax

It is vital for those who know about climate change to help others reach the same understanding regarding the matter. To help people understand, show them the basic facts that we have already established above:

Climate change is supported by multiple lines of evidence: The science of climate change is based on a wide range of evidence from different fields of research. These lines of evidence all point to the conclusion that the Earth's climate is changing and that human activities are major contributing factors.

Climate change is supported by a consensus of scientific experts: The overwhelming majority of climate scientists agree that climate change is happening and that human activities are a significant cause. This consensus is supported by numerous scientific organizations- including the National Academy of Sciences, the American Association for the Advancement of Science, and the Intergovernmental Panel on Climate Change.

Climate change is already having observable impacts: The effects of climate change, such as rising temperatures, more frequent heat waves, melting glaciers, and rising sea levels, are already being observed around the world. These changes are consistent with the predictions of climate models, which are based on our understanding of the physics of the Earth's climate.

Conclusion

Based on discussed above, climate change is a complex issue that has far-reaching impacts on our planet. The scientific consensus is clear that the Earth is warming at an unprecedented rate, and that this warming is primarily caused by human activities such as burning fossil fuels and deforestation. The consequences of climate change are already being felt around the world, with rising sea levels, more frequent and severe extreme weather events, and changes to ecosystems and biodiversity.

Despite the overwhelming evidence, there is still a significant amount of public skepticism and confusion surrounding climate change. This underscores the need for continued education and outreach to help people understand the science behind climate change and the urgent need for action to address this global challenge.

The good news is that there are steps we can take to reduce our greenhouse gas emissions and mitigate the impacts of climate change, such as transitioning to renewable energy sources and adopting more sustainable land use practices. By working together and taking action now, we can help to ensure a more sustainable future for ourselves and future generations.

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