Expert Opinion: What is Climate Change? Has it happened before? Why is it important now?

With the UK hosting a global summit on the climate crisis in November, and sustainability increasingly moving up the business agenda, Stockport’s renewable energy specialists, KAST Energy, answer some frequently asked questions to explain what exactly is climate change, and why businesses and individuals should care.

Article by Kes Scott, KAST

What is climate change?

Climate is the average weather in a place over many years. Climate change is when we experience a shift in those average conditions and, due to global rises in temperature, the Earth is in a state of rapid climate change now.  

Our planet provides a life support system for many different forms of life. We live largely in man-made cities but where does the energy we need to live, to light up those cities come from?

Energy cannot be created or destroyed; it can only be transformed from one kind to another. Right now, most of that energy comes from burning fossil fuels (coal, oil, and natural gas) that have been buried under the ground for millions of years.

Are humans responsible for the acceleration of climate change?

There is now no doubt that human activity has added to the natural greenhouse effect by artificially increasing the quantity of greenhouse gases in the atmosphere. Most well-known is carbon dioxide; its concentrations have spiralled because of burning fossil fuels such as coal, oil, and gas. With raised levels of greenhouse gases in our atmosphere, more and more heat energy is trapped and our Earth becomes warmer. This process is known as ‘global warming’.

What is the Green House effect?

The atmosphere is made up of layers of various gases around the Earth including water vapour, carbon dioxide, methane, and nitrous oxide – more commonly called “Greenhouse Gases”. In the right mixture these gases help warm the Earth by a natural process known as the greenhouse effect. The sun’s rays penetrate the Earth’s atmosphere and the Earth’s surface absorbs the heat energy, warming it. Heat is then released from the surface. Some of this energy escapes back into space, but, because of Greenhouse gases, much of it remains in the atmosphere trapping energy and warming the planet sufficiently to support life.

There is now no doubt that human activity has added to the natural greenhouse effect by artificially increasing the quantity of greenhouse gases in the atmosphere. Carbon dioxide concentrations have spiralled because of excessive burning of fossil fuels. Global average surface temperatures have reached around 1°C above pre-industrial levels.

What are the factors responsible for our rapid climate change?

Scientists now agree that human activities have caused 95-100% of the warming observed since 1950 (IPCC, 2013). Several factors can change the Earth’s temperature such as the strength of the sun or volcanic activity, but these only make a small and very temporary difference. Global warming is the main cause of what today we call ‘climate change’.

So why is Climate Change more important now than ever before?

As a species and society, we have structured our lives around historical and current climate conditions. We are used to our own “normal” temperature range and weather conditions, and we are sensitive to extremes that fall outside of this expected range.  Climate change has the potential to affect our society. For example, climate change could affect human health, infrastructure, and transportation systems, as well as energy, food, and water supplies.  

Who is likely to be most affected by climate change?

Some people will likely face a far greater challenge than others. Climate change could especially impact people who live in areas that are more vulnerable to coastal storms, drought, and sea level rise or people who live in poverty and older adults. Similarly, some professions and industries may face considerable challenges from climate change. Professions that are closely linked to weather and climate, such as outdoor tourism, commerce, and agriculture, will likely be especially affected.

• Over the past four decades, population has significantly grown in coastal areas in warmer climates around the world. These areas are most sensitive to coastal storms, drought, air pollution, and heat waves. 
• Along the coasts, both increasing population and changes in climate place growing demands on transportation, water, and energy infrastructure. 
• Populations in the dryer areas will face worsening water shortages and increased wildfires
• Arctic residents will likely experience challenges caused by thawing permafrost and reduced sea ice. 

What impact does climate change have on our oceans?

Even a slight, sustained increase in global warming gradually melts sea ice over time; fewer bright surfaces are available to reflect sunlight back into the atmosphere. More heat energy is absorbed at the surface and ocean temperatures rise. This begins a cycle of warming and melting. Warmer water temperatures delay ice growth in the autumn and winter, and the ice melts faster the following spring, exposing dark ocean waters for a longer period the following summer.

What impact is climate change having on oceans and marine life?

Oceans currently absorb around 30% -35% of all carbon dioxide, the more it absorbs the more acidic it becomes, and this is turn causes corals to die off, a process called bleaching. This results in a loss of habitat by some marine creatures and ecosystems which need and rely on coral reefs as shelter and sources of food. Coral reefs are also home to some of the crucial food sources for mankind. Due to the increased carbonic acid in our oceans, calcium carbonate is reduced which means that any shelled organisms will reduce, a valuable source of food for a vast ocean ecosystem.                                

Ocean currents plays an essential role in regulating Earth’s weather; when ocean currents are altered, it can have a significant impact on humanity. For example, Europe has a somewhat temperate and cold climate; this is the Atlantic current, the Gulf Stream.  The changes in Atlantic currents can greatly change the entire weather and temperature patterns for all of Europe. It can mean that dry countries may experience a prevalence in rainy seasons and changes to air temperatures.  Collectively, these factors have major implications for all species and humans.

Over the past decade we have seen more rain, more dry weather, more extreme and extended weather patterns – the certain effects of climate change.