Climate Change and Chemistry
Climate change affects humans and natural environments today and particularly in the future. In chemistry class, climate change can be looked at in relation to the structure of the atmosphere, composition and role of greenhouse gases, and energy production systems. Therefore, chemistry plays an important role in understanding climate change in-depth and building a climate-friendly world.
Chemistry of the Atmosphere
The atmosphere enables life on Earth. It is a relatively thin layer of gases surrounding our planet. The life-sustaining composition of the atmosphere is unique compared to other planets in the solar system. By volume, dry air is a mixture of various gases. Due to gravity, air density decreases with altitude. Because of photochemical reactions initiated by the absorption of energy from sunlight, the constituents of dry air vary in the different layers of the atmosphere.
The major constituents of air are nitrogen (78%), oxygen (21%), argon (1%) and carbon dioxide (0,04%). The relative concentration of gases remains constant close to the Earth’s surface. Although water vapour accounts for only a small percentage of air, it is an important gas, particularly in the lower atmosphere. Altogether, the atmosphere consists of thousands of gases, but most of them are found in much smaller proportions than the primary gases.
The Earth’s atmosphere can be divided into different layers from lowest to highest based on their temperature: troposphere (0 to 10 km), stratosphere (10 to 50 km), mesosphere (50 to 100 km) and thermosphere (100 to 500 km). In addition, air pressure and gas mixtures vary, depending on the layers and their regions.
One way to describe the characteristics of the atmosphere is to divide it into the neutral atmosphere and the ionosphere. The neutral atmosphere involves the assumption of hydrostatic equilibrium, whereas in the ionosphere (from about an altitude of 60 km) the atmosphere is partially ionized and contains free electrons. The ionosphere is ionized by shortwave solar radiation. The region around the Earth in which charged particles are controlled by the planet’s magnetic field, is called the magnetosphere (from about an altitude of 10,000 km).
Increase in Greenhouse Gases causes Climate Change
Understanding greenhouse gases, their different qualities and the greenhouse gas effect as concepts is the basis of understanding climate change, and therefore this guide provides solid information about them.
Ocean Acidification is linked to Climate Change
Environmental problems are often interconnected, and their causes and consequences form a complex web. Ocean acidification is a major environmental issue linked to climate change. They both have a common cause. Ocean acidification is caused by the uptake of excess carbon dioxide from the atmosphere, which accelerates the decrease in the pH of the Earth’s oceans. Ocean acidification is also amplified to a certain extent by nitrogen and sulphur compounds from fossil fuel combustion.
The current rate of ocean acidification is rapid and it endangers the future of many sea creatures. It is estimated that surface ocean pH has decreased by 26% since the Industrial Revolution began. The researchers have determined that the current rate of acidification is faster than at any time in the past 300 million years. The only possible response is to urgently and globally reduce CO2 emissions.
When carbon dioxide dissolves in seawater, it reacts with water molecules, creating carbonic acid. Carbonic acid in turn reacts with carbonates dissolved in seawater. This consequently means that corals and crustaceans with calcium carbonate shells or skeletons will suffer from the excess carbon dioxide humans are producing.
Many species are not able to evolve quickly enough to adapt to the rapid change and as a result, many face challenges and even mass extinction. This would pose a massive threat to an entire ecosystems and food production chain. Those facing the greatest risk would be the inert or slow species, such as corals, molluscs and seashells, in which impacts of ocean acidification can already be seen.
Tackling Climate Change requires Chemistry
Chemistry can play an important role in understanding the basics of climate change. Ironically, the chemical industry is a significant cause of global warming although it also may deliver potential solutions.
Talking about Climate Change in Chemistry Class
You have now read how to make use of basic chemistry to understand climate change and which problems and solutions applied chemistry has created, for example, in electricity generation. While teaching basic concepts, it is easy to get stuck on minor details or a technical perspective. However, it is good to bear in mind that climate change is a significant social issue and its consequences already have impacts on humans around the world.
Keeping the bigger picture in mind is important. Facts are not usually enough to motivate people to adjust their lifestyles. One of the core contents of the Finnish national core curriculum is to encourage students to become active citizens, who are aware of climate change and want to take action in the fight against it. Therefore, it is important to teach influencing skills, which can easily be linked to different aspects of energy politics. In addition, be prepared to discuss emotions and experiences related to climate change.
Climate change debates often highlight personal choices and consumer habits, particularly when addressing young people. This approach has its place, but there are more effective ways to make a difference, such as acquiring skills and sound knowledge, launching citizen initiatives, making speeches, writing articles and letters to editor, contacting decision-makers and organizing meetings. The more you practice influencing skills, the better you get.