A brief introduction to climate change and four of its key facets: weather, climate, the greenhouse effect, and global warming.
Wednesday, September 16, 2020
By Michael Schwebel
4 Key Areas to Know About Climate Change
Climate change is one of the most important issues facing the world today. However, what climate change is and the factors that contribute to it are complex and easy to misunderstand. Here is a brief introduction to climate change and four of its key facets: weather, climate, the greenhouse effect, and global warming. At the end, you’ll have a better understanding of how these four areas interact with one another and relate to the critical topic of climate change.
Weather refers to the current and near-term conditions of wind, air pressure, temperature, humidity, precipitation, and other quantifiable variables. Weather is typically measured and forecasted over short time periods ranging from a fraction of a second to minutes, hours, and days. While weather forecasts can extend to weeks or months, their accuracy tends to diminish as the forecast period lengthens.
Climate is the prevailing weather or weather patterns in a location or region over a long period. There is no strict rule as to when weather becomes climate. Rather, an area’s climate is based on trends over time, such as decades or centuries, while its weather is based on short-term observations or forecasts. Weather forecasts, in turn, draw upon knowledge of the area’s typical climatic behavior. Sometimes there are semi-regular climatic occurrences known to create distinct weather patterns — such as El Niño or La Niña — yet it is important to remember that understanding climate is to comprehend the prevailing weather, meteorological, Earth system processes, and behavior for a location for the long term.
The greenhouse effect is the natural process that warms the earth. Simply put, there are naturally-occurring greenhouse gases (GHGs) in our atmosphere, such as carbon dioxide, water vapor, and methane, that trap energy from the sun (solar radiation), giving our Earth a livable temperature. If you’re familiar with a pinball machine, imagine the silver ball represents solar energy and those vibrating-when-struck bumpers are the GHGs. The silver ball may pass through the maze of bumpers unencumbered, representing incoming or outgoing solar radiation not captured by GHGs. But, more frequently, the ball gets trapped by bumpers and spends time ricocheting about. The same can be said about GHGs trapping the solar radiation. Historically GHGs in the atmosphere reflected and absorbed some of the incoming and re-radiated energy, sustaining life on the planet. However, that equilibrium is changing due to the increasing number of GHGs that are being released into the atmosphere.
Global warming is the net warming of the Earth’s atmosphere that is largely the result of a human-enhanced greenhouse effect. Just imagine that pinball machine with many additional bumpers; it would be quite a long time until the silver ball emerged from the dense labyrinth of bumpers. Likewise more GHGs in the atmosphere trap more incoming and outgoing solar radiation, leading to a more heated planet: an enhanced greenhouse effect.
On top of this, overall global warming creates a domino or knock-on effect that impacts naturally occurring processes such as temperature, snowfall, and ice accumulation. The cycle goes as follows: rising temperatures, due to an enhanced greenhouse effect, leads to greater warming, which then creates more severe weather and climate ramifications. This is known as a positive feedback loop, with the word positive not meaning beneficial but instead a growing destabilizing force. As this cycle grows more intense, the repercussions become more destructive. While there are naturally occurring events that can enhance or diminish the greenhouse effect, as well as efforts known as geoengineering that aim to reduce the amount of global warming, the majority of global warming is attributed to human activities.
What is Climate Change?
Climate change is not the weather, the climate, the greenhouse effect, or even global warming, although it involves all of these. Rather, climate change refers to how the Earth’s climate is being changed by global warming resulting from a human-enhanced greenhouse effect and how those changes are observable in altered climate and weather patterns. Climate change has profound but unequal effects across the globe — from extreme temperatures to violent storms, droughts, and floods. Disparities in the impact from these effects, and inequalities, can become even more pronounced due to differing vulnerabilities and adaptative capacities that exist upon our Earth.
Weather, climate, the greenhouse effect, and global warming are some of the key pillars of climate change. Though there are many other factors that influence climate change, understanding these terms and how they interact with one another are critical to developing knowledge around how the climate system works, and the causes, impacts, and potential solutions to climate change.