What is climate change?

Ariana Lutterman is one of our Emerging Fellows. She and our other Emerging Fellows will be posting throughout the year. Her first article seeks to clarify what climate change is and its implications for the present and the future. Climate change is often cited as the most pressing problem facing humanity today. To truly understand its implications, it’s important to first understand its language. Here I hope to present a framework for how climate change has been defined through a process of international scientific consensus as well as how human actions are implicated in what we are currently observing as climate change. Climate is weather over time, the earth’s climate is a combination of climates across the planet, and planetary climate change is a change in the earth’s climate over an extended period of time. Phrased slightly differently, planetary climate change is a change in the combined climates made up of combined weather around the planet over a long period of time. Everyone anywhere experiences weather on a daily basis, and while everyone on the planet is affected by planetary climate change, its effects are infinitesimally small and often more intangible. Global warming, a rise in the average global temperature, is one measure of planetary climate change. Often used interchangeably, global warming is just one measure of climate change. As the name suggests, it is an overall rise in planetary climate change, but this is only one aspect of what climate change means. The daily lived experience of climate change may, in many areas, look like cooler seasonal temperatures or more frequent cold weather events. So climate change as a term indicates that not only warming is occurring but also a host of other fluctuations to the usual planetary weather patterns. The earth’s climate is constantly changing. Historically there have been periods both warmer and cooler than now. These fluctuations have resulted from natural processes like variations in Earth’s distance and energy received from the sun, volcanic eruptions, plate tectonics, and changes in earth’s oceans. There is a distinction between this natural climate change variability and what we are now observing. Current observable climate change is occurring much more rapidly than any historic climate event. It is this speed of change we are currently observing with which scientists are concerned. It is this that is attributed primarily to human activities. The primary anthropogenic, or human-induced, contribution has been a dramatic increase in carbon dioxide (CO2) since industrial times largely through the burning of fossil fuels (oil, coal, natural gas). Though a misnomer (not actually the mechanism through which a greenhouse functions), the greenhouse effect describes how solar radiation trapped by a planet’s atmosphere warms the surface. Human actions since the industrial era have dramatically increased the number of atmospheric greenhouse gases. This anthropogenic greenhouse effect is caused primarily by actions like burning fossil fuels, agriculture, and deforestation which significantly increase atmospheric concentrations of carbon dioxide, methane, and nitrous oxide and cause higher than normal rates of solar radiation to become trapped by the atmosphere. I plan to follow the international scientific community’s consensus in recognizing climate change as referring to planetary and anthropogenic changes to climatic patterns. Climate change is a part of a complex system of Earth processes, and its consequences manifest in similarly systemic ways. It represents not only an environmental crisis, but a social, economic, and cultural crisis as well. © Ariana Lutterman 2017