Global warming affects evapotranspiration—the movement of water into the atmosphere from land and water surfaces and plants due to evaporation and transpiration— which is expected to lead to: Increased drought in dry areas.
Heavy rainfall is one of the most frequent and widespread severe weather hazards to affect New Zealand. It is defined as rainfall greater than 100 mm in 24 hours. Often, a significant amount of precipitation occurs in only a few hours, leading to severe flooding and landslide risk.
If the forecaster is only 50% sure that precipitation will occur, and expects that, if it does occur, it will produce measurable rain over about 80 percent of the area, the PoP (chance of rain) is 40%. ( PoP = . 5 x . 8 which equals .
When little or no rain falls, soils can dry out and plants can die. When rainfall is less than normal for several weeks, months, or years, the flow of streams and rivers declines, water levels in lakes and reservoirs fall, and the depth to water in wells increases.
The volume of rain that falls in a heavy shower depends on the amount of water vapour in the atmosphere. At higher temperatures the atmosphere may contain more water vapour, thus increasing the chance of heavy showers. The various types of precipitation are created in different processes in the atmosphere.
How to (Try to) Make It Rain
- Seeding the Sky. The most widely used weather-modification technique is probably cloud seeding, which involves priming clouds with particles of silver iodide.
- Rain Rockets. Airplanes aren't the only way to seed clouds.
- The Atmosphere Zapper.
- Ice-Breaking Booms.
- Riding the Lightning.
Changing Rain and Snow Patterns
As temperatures rise and the air becomes warmer, more moisture evaporates from land and water into the atmosphere. That's because climate change causes shifts in air and ocean currents, which can change weather patterns.Within a cloud, water droplets condense onto one another, causing the droplets to grow. When these water droplets get too heavy to stay suspended in the cloud, they fall to Earth as rain. Water vapor turns into clouds when it cools and condenses—that is, turns back into liquid water or ice.
Drought also affects the environment in many different ways. Plants and animals depend on water, just like people. When a drought occurs, their food supply can shrink and their habitat can be damaged. Sometimes the damage is only temporary and their habitat and food supply return to normal when the drought is over.
Rainfall intensity is classified according to the rate of precipitation, which depends on the considered time. Heavy rain — when the precipitation rate is > 7.6 mm (0.30 in) per hour, or between 10 mm (0.39 in) and 50 mm (2.0 in) per hour. Violent rain — when the precipitation rate is > 50 mm (2.0 in) per hour.
Heavy Rain & Flooding. More heavy rain is one of the hallmark signs of climate change. As the atmosphere warms, more water evaporates from soils, plants, lakes, and oceans. So when this additional water vapor condenses into precipitation, it leads to heavier rain — or when cold enough, heavier snow.
Here are a dozen easy, effective ways each one of us can make a difference:
- Speak up!
- Power your home with renewable energy.
- Weatherize, weatherize, weatherize.
- Invest in energy-efficient appliances.
- Reduce water waste.
- Actually eat the food you buy—and make less of it meat.
- Buy better bulbs.
- Pull the plug(s).
For example, you can expect snow in the Northeast in January or for it to be hot and humid in the Southeast in July. This is climate. The climate record also includes extreme values such as record high temperatures or record amounts of rainfall. Climate, however, is the average of weather over time and space.
Urban and industrial air pollution can stifle rain and snowfall, a new study shows, because the pollution particles prevent cloud water from condensing into raindrops and snowflakes. The droplets' small size is caused by pollution particles that act as "seeding" sites around which cloud moisture condenses.
