Most climate change is attributed to very small variations in Earth’s orbit, which affect the amount of solar energy we receive. But the current warming trend is increasing at a rate unseen within the past 1,300 years (NASA).
Did you know? Sea levels rose 17 centimeters in the last century, but they have more than doubled in the last decade.
How do we know it’s happening?
- Rising sea levels
- Rising global temperatures
- Warming oceans
- Shrinking ice sheets
- Declining Arctic sea ice
- Ocean acidification
What is the effect?
How hot were you this past summer? You weren't alone—currently, the U.S. is suffering from the worst drought since 1956 with over half of the country suffering from “moderate to extreme” drought (National Climatic Data Center).
The flow of the Mississippi River has slowed, allowing saltwater to enter from the Gulf and threaten community water supplies. The lack of rain is affecting corn crop, too, and this past July, 58,000 fish were found dead along a 42-mile stretch of the Des Moines River in Iowa due to heat.
Water, already a valuable resource, is in demand—less than 1 percent of water is available to meet the world’s water needs, and one-third of the world’s population live in areas the World Bank characterizes as “water stressed.” (Sustainable Water)
- Avoid washing your car.
- Conserve water in your yard. To minimize evaporation, water in the early morning when temperatures are cooler.
- Don’t leave the water running when you brush your teeth.
- Don’t run the dishwasher until it’s overflowing.
- Shorten your showers.
- Use a broom instead of a hose to clean sidewalks.
Did you know? If you shorten your shower by one minute, you’ll save nearly 1,000 gallons of water a year.
What’s causing the change?
Sunlight warms the Earth’s surface—most of the heat is absorbed by greenhouse gases and re-emitted in all directions.
The average amount of energy coming from the sun has either remained constant or increased slightly since 1750 so if the sun caused an increase in warming, we would see warmer temperatures in all layers of the atmosphere not just the greenhouse gas layer.
Did you know? For 650,000 years, atmospheric carbon dioxide (CO2) levels have never been above 300 parts per million until NOW. Check out the graph from NASA.
What are Greenhouse Gases?
- Water vapor: increases as Earth's atmosphere warms
- Carbon dioxide (CO2): result of volcano eruptions and human activities such as deforestation, land use changes, and burning of fossil fuels
- Methane: result of natural sources and human activities such as landfill use, agriculture practices, and management of domestic livestock manure
- Nitrous oxide: result of soil cultivation, fossil fuel combustion, nitric acid production, and biomass burning
- Chlorofluorocarbons (CFCs): synthetic compounds of entirely industrial origin; already regulated due to its destruction of the ozone layer
Did you know? When the U.S. was covered by more than 3,000 feet of ice in the last ice age, temperatures were only five to nine degrees cooler than today.
The consequences of changing the concentration of atmospheric greenhouse gases will result in a warmer Earth, new climate patterns, disrupted crop/plant cycles, and increased sea levels.