Climate Change: What are fossil fuels, and how do they harm the planet?

How are they formed, and why are they so problematic? Here is everything you need to know.

The production platform of Leviathan natural gas field is seen in the Mediterranean Sea, off the coast of Haifa (photo credit: REUTERS/AMIR COHEN)
The production platform of Leviathan natural gas field is seen in the Mediterranean Sea, off the coast of Haifa
(photo credit: REUTERS/AMIR COHEN)

Fossil fuels are the most commonly used form of energy in the world. However, they have come under increased scrutiny in recent years, amid growing awareness of climate change, pollution and renewable energy.

But what are fossil fuels exactly? How are they formed, and why are they so problematic?

Here is everything you need to know about fossil fuels. 

What are fossil fuels? How are fossil fuels formed?

The term fossil fuels refers to any kind of fuel that is formed from dead plant or animal remains, hence the term "fossil," which is also why they are known as hydrocarbon fuel. They become fuel after these dead life forms undergo anaerobic decomposition, which can take hundreds of millions of years. 

Malfunction at oil refinery in Haifa, May 26, 2021 (credit: ENVIRONMENTAL PROTECTION UNION IN HAIFA)Malfunction at oil refinery in Haifa, May 26, 2021 (credit: ENVIRONMENTAL PROTECTION UNION IN HAIFA)

These fuel sources are either mined, drilled for or otherwise extracted from underground. This can be done in a variety of ways depending on the specific type of fossil fuel in question.

What are examples of fossil fuels?

There are many different types of fossil fuels. However, the main ones are coal, oil (petroleum) and natural gas. These are extracted in a variety of ways and are used as fuel or converted into other forms of energy such as electricity. Of these main fossil fuels, petroleum is the most prominently used worldwide.

Many fossil fuels are also further refined or turned into other derivative products. Some of these refined fuels include propane, gasoline and kerosene, while fertilizers and plastics are common derivatives. 

These fuel sources are not renewable, due to the nature of their formation. As such, they are considered nonrenewable resources.

Why are fossil fuels bad? How do fossil fuels affect global temperatures?

Fossil fuels are extremely damaging to the environment, and this is not just in their use. Extracting and transporting fossil fuels alone cause severe damage from the start. Mining and fracking (hydraulic fracturing of bedrock to facilitate oil and gas extraction) cause degradation to the land as massive swathes of land, such as entire mountaintops, can be blasted away to find coal or oil, and the land does not go back to normal, damaging the local ecosystem and ruining wildlife habitats.

Mining and fracking operations also severely impact the water, with acid runoff, rock dumping and oil spills causing severe damage and pollution to all bodies of water. Fracking in particular is also known to be able to contaminate local drinking water, and the produced wastewater can cause waterways to be polluted with heavy metals and radioactive materials.

The effects these pollutants have can be severely damaging to humans, and studies have shown links to various health issues such as birth defects and cancer.

Mining also causes severe air pollution, which has been linked to many types of cancer, impacting millions worldwide.

Burning fossil fuels is the most damaging, however. When fossil fuels are burned, they release carbon dioxide into the atmosphere, as the carbon combines with oxygen in the air. This is because the fossil fuels themselves were formed from once-living lifeforms, which naturally contain carbon, as does all life. Carbon dioxide, as a greenhouse gas, heats up the atmosphere and raises global temperatures.

Other pollutants are released in this process as well. For example, according to the US Environmental Protection Agency (EPA), coal power plants produce 42% of mercury emissions and two-thirds of sulfur dioxide emissions in the country, both of which are incredibly damaging. 

A big part of this problem is also how the carbon dioxide released by burning fossil fuels is dealt with. Through a phenomenon known as the Carbon Cycle, the planet actually has the means of absorbing and dealing with released carbon dioxide, especially through ocean absorption. But it can only absorb so much, and the amount released by burning fossil fuels vastly exceeds this comparatively small limit, leaving the unabsorbed gases in the atmosphere.

According to the US Department of Energy, concentrations of carbon dioxide have increased by around 40% since the mid-19th Century, around the time of the industrial revolution. Emissions, though, have drastically spiked since the 1950s.

As noted by the Intergovernmental Panel on Climate Change, "It is extremely likely that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas concentrations and other anthropogenic forcings together."

What are the benefits of renewable energy?

Renewable energy resources are, in theory, far more beneficial due to their virtually unlimited supply, as well as not being as harmful to the environment compared to fossil fuels. These include solar energy, which relies on the Sun, and wind energy, which is used by the wind powering wind turbines. This efficiency is noted, with wind energy in particular creating 1164% of of its input when turned into electricity, compared to coal's 29%, as noted by the Wall Street Journal.

Clean energy resources are also booming economically, with jobs in the sector increasing over the years as further advancements are made. Renewable energy is also becoming cheaper and cheaper, and it is possible to integrate it with existing systems. 

Cutting back significantly on fossil fuel usage is very possible in theory, and is why many countries have committed to drastically reducing their carbon footprints. It is also the subject of two of the United Nation's Sustainable Development Goals (SDGs).

To use the US as an example, a recent report by the nonprofit Natural Resources Defense Council (NRDC) found that it is possible to cut US fossil fuel usage by 80% by 2050, should the US reduce energy demand, invest in renewable energy and transition transportation to being more electric-based rather than relying on fossil fuels. 

However, there are road blocks interfering with this change. These include the expense and difficulties many face regarding installing wind turbines and solar panels, as well as the political and economic clout of many firms in the well-established coal, oil and natural gas industries. In particular, there are many countries who base much of their economies on fossil fuels, especially in the oil and natural gas-rich Middle East.

What about nuclear?

Nuclear energy is another factor to consider, as while it is not a fossil fuel or a renewable energy source, it is carbon-free and very efficient. As noted by the US Office of Nuclear Energy, nuclear power is very reliable, and has supplied a fifth of US energy annually since 1990. Its capacity factor is very high, producing several times more energy than natural gas and coal, and is more reliable than wind and solar.

Many scientists have suggested solving the fossil fuel-induced climate crisis by making a drastic shift to nuclear power worldwide.

But this solution has its detractors as well.

As noted by the German Green political foundation Heinrich-Böll-Stiftung, there are several issues, such as the time frame to make a nuclear power plant – meaning 93 million people could die in the interim – the fact that they are incredibly expensive both in terms of cost and the damage they could cause in a nuclear reactor core meltdown and the risks of increasing nuclear weapon proliferation, cancer in uranium miners and radioactive waste, as well as the possibility of a catastrophic meltdown, such as what happened in Chernobyl.

Ultimately, many view renewable energy as a safer and more efficient alternative due to cost, time and limited risk of causing damage in a severe meltdown.