AMG BRIEFING NOTE[tw-divider][/tw-divider]

[tw-column width=”one-half”]How much do we really know about the causes of climate change and its impacts? This simplified AMG backgrounder provides an introduction to the scientific and political dimensions to climate change, as a reference point for future coverage on this issue.[/tw-column]

Climate change simply refers to a significant change in climate that occurs over a period of decades, or longer. Two types of climate change exist: natural climate change and anthropogenic climate change.
Natural fluctuations in global temperature occur as a result of changes in solar activity, the Earth’s orbit and volcanic eruptions, with the clearest, most-extreme depiction depicted being seen in the Ice Age millions of years ago.

Anthropogenic climate change – or climate change caused by humans – is the change in climate that occurs as a result of the release of harmful gases into the atmosphere; gases popularly known as greenhouse gases (GHGs). And when it comes to GHGs, the four major emissions are carbon dioxide, nitrous oxide, methane and fluorinated gases.

Once released, GHGs do not easily disappear from the atmosphere and this is particularly concerning given their ability to trap heat emitted by the sun. Each GHG that is released is a heat trapping molecule floating in the atmosphere. And eventually, an accumulation of these warming molecules cause an increase in the atmospheric temperature, and the effects of increased atmospheric temperatures ultimately result in climate change.

Where do GHGs come from?

Carbon dioxide, methane and nitrous oxide are all primarily released when fossil fuels are burned as a source of energy/power for electricity and transport. Fossil fuels are a natural resource formed from prehistoric remains of plants and animals, which decompose to form coal, oil and natural gas. Fluorinated gases, unlike the other GHGs, have no natural sources, and are released in the atmosphere through a variety of industrial processes.

GHGs & Global Warming

Greenhouse gases have a lifespan of hundreds and even thousands of years, which means that the more they are released in the atmosphere, the longer they will be remain warming the atmosphere, resulting in what is known as global warming.

While there are other sources which contribute to the release of these gases into the atmosphere – such as agricultural activity – a greater percentage can be attributed to the burning of fossil fuels for industrial and transportation purposes.

Who releases GHGs?

Fossil fuels are constantly being relied upon as a source of energy for electricity and transport. Wherever there is energy use – unless the energy source is renewable – fossil fuels have been burned and GHGs are being released into the atmosphere. From a charging cell phone to a clothes manufacturing company, fuelling a car or a plane, fossil fuels have been burned as the source of energy.

Since we all rely on the use of fossil fuels for electricity and transport, we are all responsible for the release of GHGs in the atmosphere. However, where more electricity and transport are used, greater amounts of GHGs are released.

Disproportionate climate change impacts on low-emitting island states

As countries strive for continuous economic growth through industrial activities, the degree to which GHGs are released increases in both quantity and frequency. Consequently, the more developed countries of the world contribute greatest to GHG emissions because of their level of industrial activities and their high density of transportation. Currently, the countries with the highest GHG emissions are China, the United States of America, states within the European Union and India.

Unfortunately, the effects of GHGs released into the atmosphere are not only felt in the areas where they have been released: gas molecules travel in the atmosphere and their impacts are felt globally. In fact, the nations that are most greatly impacted by global warming are Small Island Developing States (SIDS) and here in the Caribbean, the effects of global warming are becoming more apparent and evident with each year.

Observations directly linked to global warming, and ultimately climate change, are:

  1. Rising atmospheric temperatures i.e. hotter days
  2. Change in rainfall patterns: e.g. heavy precipitation and drought
  3. More frequent and extreme weather events i.e. hurricanes
  4. Rising sea levels resulting in floods and contamination of fresh water sources
  5. Increased ocean acidity, damaging coral reefs
  6. Increasing ocean temperatures, causing migration of fish and damaging coral reefs

The Caribbean’s future in a warming planet

Fortunately, there is an alternative source of power for energy generation. Renewable ‘clean’ energy generates power just like fossil fuels do, without the consequence of polluting the atmosphere with GHGs. Types of renewable energy that can be used are bio-energy, solar, wind, geothermal, hydropower and ocean energy. The use of clean energy for electricity and transport in countries where fossil fuels are heavily relied upon will significantly decrease the levels of GHG emissions, and reduced GHG emissions will slower the rate at which global temperatures increase and ultimately alleviate the impacts felt by the most afflicted islands in the future.

Some have questioned whether these observed climatic changes are as a result of human action, or natural climate change. The Intergovernmental Panel on Climate Change (IPCC) addressed this doubt and concluded that “while many factors continue to influence climate, scientists have determined that human activities have become a dominant force, and are responsible for most of the warming observed over the past 50 years.”

Scientists have warned that in order to prevent irreversible damage to the planet, GHG emissions should be kept at levels that ensure a global temperature increase of no more than 2oC/35.6oF by the end of the century.

However, Caribbean islands, much like other SIDS, are at risk of irreversible damage if temperatures increase by more than 1.5 oC/34.7oF. If global temperatures continue to increase, the social, economical and physical impacts will become increasingly severe. The Caribbean and other SIDS will constantly have to find resources – both human and financial – for restoration, following the impacts of climate change and to prevent further damage to islands already affected.

The implications of climate change are costly in both mitigation and adaptation stages. SIDS are currently trying to do their part by converting to renewable energy use to prevent further GHG emissions. Adapting to the effects of climate change, such as hurricane damage, also places a financial burden to these less developed nations.

When it comes down to it, larger countries contribute greatest to GHG emissions in order to achieve economic growth, yet they feel only a small portion of the climate change impacts. SIDS contribute negligibly to GHG emissions, yet feel the brunt of climate change impacts. The onus is on the larger emitters to commit to GHG emission reductions in order to save our planet from irreversible damage and to offer support to smaller nations to assist in their mitigation and adaptation needs.

Understanding climate change in the Caribbean context

Sophia Longsworth

Sophia is a Grenadian residing in the United States. She holds an MPH and an MSc. in Natural Resource and Environmental Management, and has research interests in the impact of the environment on public health.

Category: Sustainability