One of the recent webinars EarthConnection hosted was entitled “The Realities of Climate Change (and how to respond to climate change deniers)”. Because this topic is so important and not everyone had the opportunity to view the webinar, I am going to use this blog to present some of the information.

There is sometimes confusion between “weather” and “climate”. Weather is short term, in a limited area, can change rapidly, and is sometimes difficult to predict. Climate, on the other hand, is long term, covers a wide area, refers to seasonal changes, and is measured over long periods of time. It is the difference between what’s happening outside your window (weather) and what is happening to the planet as a whole over decades (climate).

There has always been a natural greenhouse effect which, for thousands of years, showed a balance between solar radiation entering Earth’s atmosphere during the day and at night when Earth’s surface cools releasing some of the heat back into the air. The greenhouse effect is actually one of the things that makes life on our planet possible. As long as there is a balance between the heat coming to earth and that released back into the atmosphere, optimum conditions for life on Earth remain.

However, human activities, primarily the use of fossil fuels, have increased the amount of carbon dioxide and other greenhouse gases (methane, nitrous oxide) into the atmosphere. This traps more heat on the Earth’s surface and causes global warming.

The term climate change refers to all of the changes that are taking place on our planet as a result of global warming. These include the following: stronger storms, damaged coral, rising sea levels, warmer oceans, changes in plant life cycles, thawing permafrost, melting glaciers, more droughts and wildfires, higher temperatures and more heatwaves, changes in animal migration and life cycles, and changing rain and snow patterns.

In his encyclical Laudato Si’, Pope Francis states that “A very solid scientific consensus indicates that we are presently witnessing a disturbing warming of the climatic system. In recent decades this warming has been accompanied by a constant rise in the sea level and, it would appear, by an increase of extreme weather events, even if a scientifically determinable cause cannot be assigned to each particular phenomenon…The problem is aggravated by a model of development based on the intensive use of fossil fuels, which is at the heart of the worldwide energy system. Another determining factor has been an increase in changed uses of the soil, principally deforestation for agricultural purposes.” 

Ninety-seven percent of the world’s climate scientists agree that climate change is a reality and, if not addressed on a global level, will have catastrophic consequences. Atmospheric carbon dioxide concentrations are higher today than at any time in at least the past 650,000 years. They are about 35% higher than before the industrial revolution, and climate scientists concur that this increase is caused by human activities, primarily the burning of fossil fuels.

The Paris Agreement was the first international agreement signed by all but two countries in the world (Nicaragua because they did not feel it went far enough and Syria because they did not attend the Paris session due to the war in their country) which addressed climate change. Each country submitted what it committed itself to do to help mitigate the effects of climate change. It is important to note that there was no mechanism for enforcement and there would be no penalties if a country did not fulfill its commitment. The agreement represented the recognition that climate change was changing the earth’s atmosphere and that it was a global problem. The United States has since withdrawn from the agreement stating that the cost was too high although there were no external costs imposed. It was a voluntary agreement submitted by our government.  Since the U.S. is the second-largest polluter in the world (after China) it is extremely unfortunate that we are not willing to work toward global solutions.

Pope Francis states clearly that “Climate change is a global problem with grave implications…It represents one of the principal challenges facing humanity in our day.” He speaks often of the connection between climate change and poverty and frequently notes that those least responsible for the pollution will be most affected by it.

It is important to understand the nature of climate change in order to counteract the voices that deny it. Care for creation is one of the principles of Catholic Social Teaching and was recently named by Pope Francis as both a Corporal and Spiritual work of mercy. Not only the Catholic Faith, but every religious tradition holds care for creation as a sacred act.

An excellent resource on climate change is entitled Cranky Uncle vs. Climate Change by Dr. John Cook. Dr. Cook is not only a scientist but also a cartoonist, so his book has multiple cartoons which make the science of climate change as well as the position of climate change deniers easy to understand. You can read more about his book as well as view many of his cartoons at skepticalscience.com.

The next several blogs will explore the effects of climate change around the world with up to date information from climate scientists. Dr. Cook says that one of the difficulties with climate change is that it is not perceived of as an immediate danger and, therefore, it is easy to ignore. However, these scientists are also telling us that we are reaching tipping points which cannot be reversed and will drastically alter the conditions for life on Earth.