Climate Change Basics

Reducing greenhouse gas emissions involves multiple lifestyle changes. Using public transit or biking reduces transport emissions, eating less meat and dairy lowers agricultural impact, and educating others helps spread awareness. Therefore, all of these actions contribute to making a positive difference.

The ozone layer absorbs the majority of the Sun's high-frequency ultraviolet (UV) light. This shielding protects living organisms from harmful radiation that can cause skin cancer and cataracts. The ozone hole is not the primary driver of global climate change.

Climate change affects different regions in diverse ways due to local geography and atmospheric patterns. For example, some areas will experience severe droughts and heatwaves, while others may face increased flooding and heavier rainfall.

Weather refers to the short-term, day-to-day conditions of the atmosphere in a specific place. A single record cold day is a short-term atmospheric event, whereas long-term averages and regional characteristics describe climate.

Modern meteorology and climatology rely on a vast network of data collection methods. This includes satellite observations from space, land-based weather stations, and oceanographic instruments like buoys and drifters.

Climate is defined as the average weather conditions in a specific region over a long period, typically 30 years or more. A 50-year average temperature represents climate, while individual storms, hot days, or foggy days represent short-term weather events.

Walking, biking, and swimming rely on human muscle power and do not burn fossil fuels, meaning they do not produce greenhouse gases. In contrast, driving cars, raising livestock, and burning fossil fuels for electricity are major sources of carbon dioxide and methane emissions.

While rising temperatures, melting ice, and changing storm patterns are direct physical indicators of global warming, an increase in wild animal diversity is not a standard observation used to measure global temperature rise. In fact, climate change often threatens biodiversity.

Scientists can trace the rise of atmospheric carbon dioxide directly to human activities, such as burning fossil fuels, through isotopic analysis and historical emissions data. This correlation, along with physical models, confirms that human actions are driving modern global warming.

Greenhouse gases trap heat radiating from the Earth's surface that would otherwise escape into space. When the concentration of these gases increases, more heat is retained, leading to an increase in average global temperatures.

The Sun provides the vast majority of the energy that drives Earth's climate system, powering atmospheric circulation, ocean currents, and the water cycle. Internal heat from the Earth and human energy generation contribute negligible amounts of energy to the climate system by comparison.