But before we get too far into floods, let’s talk for a minute about greenhouses. Certain gases in the atmosphere — we call them greenhouse gases — help to keep Earth warm by trapping heat from the sun, just like a greenhouse does. Without greenhouse gases, Earth would be too cold to support life as we know it.
However, scientists are measuring higher-than-normal levels of greenhouse gases, which are being trapped in Earth’s atmosphere. Our greenhouse, our planet, is becoming too warm because of the increasing level of greenhouse gases. We’re not cooling off enough. As the North Pole warms up, it’s easier for high-pressure systems from the ocean to move in on cold air in the North Pole and push it south.
And that’s where climate effects such as storms and floods come in. For example:
- Oceans are warmer: Water takes up more space as it heats and it has to go somewhere. And it’s rising up on shorelines.
- Global air and wind currents are warmer: When air currents of high and low energy collide, they produce storms. Warmer air means more frequent and violent storms. Warm oceans also add to overheating air and wind currents.
- The North Pole is warmer: Glaciers are melting into the ocean, adding to the amount of water.
Now for some fast facts about floods:
- Floods can come on rapidly, such as a flash flood, or slowly build up, such as a rising creek during a slow, steady rainfall.
- Flooding can spread over large areas or occur over a small area.
- Floods have many causes, including rainfall, snow melt, a rising body of water or a broken dam.
- During a flood, shallow creeks streams or dry beds can become very deep. Roads can become torrential rivers washing away vehicles and people. Don’t get in, don’t take that chance!
- You may see an increase of unwanted “guests” after a flood, such as mosquitoes. Mosquito bites aren’t only annoying, they can spread dengue, West Nile virus or chikungunya, among other diseases.
For tips on preparing for floods and cleaning up after, check out these tips from APHA’s Get Ready campaign.