In fact, almost all rain that falls on land starts off in the ocean. The tropics are particularly rainy because heat absorption, and thus ocean evaporation, is highest in this area. Major current systems typically flow clockwise in the northern hemisphere and counterclockwise in the southern hemisphere, in circular patterns that often trace the coastlines. Ocean currents act much like a conveyor belt, transporting warm water and precipitation from the equator toward the poles and cold water from the poles back to the tropics.
Home Ocean Exploration Facts How does the ocean affect climate and weather on land? The sea affects the climate of a place. Coastal areas are cooler and wetter than inland areas. Clouds form when warm air from inland areas meets cool air from the sea. The centre of continents are subject to a large range of temperatures.
In the summer, temperatures can be very hot and dry as moisture from the sea evaporates before it reaches the centre of the land mass. Ocean currents can increase or reduce temperatures. The diagram below shows the ocean currents of the world view original source map. The main ocean current that affects the UK is the Gulf Stream. S coast, and from there to the British Isles. The Gulf of Mexico has higher air temperatures than Britain as it is closer to the equator.
This means that the air coming from the Gulf of Mexico to Britain is also warm. However, the air is also quite moist as it travels over the Atlantic ocean. This is one reason why Britain often receives wet weather. The Gulf Stream keeps the west coast of Europe free from ice in the winter and, in the summer, warmer than other places of a similar latitude. Winds that blow from the sea often bring rain to the coast and dry weather to inland areas.
Winds that blow to Britain from warm inland areas such as Africa will be warm and dry. Winds that blow to Britain from inland areas such as central Europe will be cold and dry in winter. Britain's prevailing i. These winds are cool in the summer, mild in the winter and tend to bring wet weather.
Climate can be affected by mountains. Mountains receive more rainfall than low lying areas because as air is forced over the higher ground it cools, causing moist air to condense and fall out as rainfall. The higher the place is above sea level the colder it will be.
This happens because as altitude increases, air becomes thinner and is less able to absorb and retain heat. That is why you may see snow on the top of mountains all year round. How precipitation is changing in the U. The colors on the map show annual total precipitation changes for compared to the average, and show wetter conditions in most areas.
The bars on the graphs show average precipitation differences by decade for relative to the average for each region. The far right bar in each graph is for Image: Adapted from Peterson et al. By changing air temperatures and circulation patterns, climate change will also change where precipitation falls. Some areas — such as the American West, Southwest, and Southeast — are expected to get drier. Meanwhile, the northern parts of the U. These precipitation projections are already becoming reality.
The Southwest, southern Great Plains, and Southeast are predicted to see more intense and prolonged droughts, according to the National Climate Assessment.
And most of the rest of the country is at risk of experiencing more severe short-term droughts, too. Researchers within the Earth Institute have found that climate change may already have exacerbated past and present droughts, and that drier conditions are making wildfires worse. Changes in precipitation patterns will challenge many farmers, as well as natural ecosystems.
Natural ecosystems, however, may not be able to adapt as quickly. The heavier bursts of precipitation caused by warmer, wetter air can lead to flooding, which can of course endanger human lives, damage homes, kill crops, and hurt the economy. The project also made projections about how flooding will change as the world continues to warm.
Climate change will make heavy downpours more frequent and more intense in many parts of the U. This means more flooding and more pollution flowing into our waterways. Heavier rainstorms will also increase surface runoff — the water that flows over the ground after a storm. This moving water may strip nutrients from the soil and pick up pollutants, dirt, and other undesirables, flushing them into nearby bodies of water.
Those contaminants may muck up our water supplies and make it more expensive to clean the water to drinking standards. The National Climate Assessment finds that water quality is already diminishing in many parts of the U. In addition, as runoff dumps sediments and other contaminants into lakes and streams, it could harm fish and other wildlife.
Fertilizer runoff can cause algae blooms that ultimately end up suffocating aquatic critters and causing a stinky mess. These conditions could harm fisheries, and make conditions unpleasant for folks who like to use lakes and streams for fishing, swimming, and other recreational activities.
Researchers within the Earth Institute at Columbia University are finding that green infrastructure, such as parks, wetlands, and other green areas, can help to absorb runoff and filter out its contaminants. Warmer temperatures and increasing acidity are making life difficult for sea creatures. These changes are transforming food chains from the bottom-up.
In addition, many fish are moving poleward in search of cooler waters, which has implications for the fishing industry and people who like to eat fish.
Temperature changes also have the potential to alter major ocean currents. Because ocean temperatures drive atmospheric circulation patterns, this could change weather patterns all over the world.
Ordinarily, as winter snowpack melts in the springtime, it slowly adds fresh water to rivers and streams and helps to replenish drinking water supplies.
However, as the air warms, many areas are receiving more of their precipitation as rain rather than snow.
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