Lesson 25 How do global weather patterns affect local weather? Part 1

Weather, which varies from day to day and seasonally throughout the year, is the condition of the atmosphere at a given place and time.

Climate is not day to day but weather collected over 1 year or many years. It is the range of a certain region’s weather.

Climate depends on latitude and geography, so it varies from place to place.

Weather and climate are shaped by complex interactions involving sunlight, the ocean, the atmosphere, ice, landforms, and living things.

These interactions can drive changes that occur over multiple time scales—from days, weeks, and months for weather to years, decades, centuries, and beyond for climate.

The ocean exerts a major influence on weather and climate.

The ocean absorbs and stores large amounts of energy from the sun and releases it very slowly.

The ocean moderates and stabilizes global climates.

Energy is redistributed globally through water currents (such as the Gulf Stream) and also through air currents(such as the jet stream).

Because ocean currents circulate water of different temperatures all over the globe, they often have a significant impact on the world’s climate and weather patterns.

The Gulf Stream is a major water current in the Atlantic Ocean.

The Gulf Stream is a warm water surface current in the Atlantic ocean that moves from south of Florida up the eastern seaboard, and then across the Atlantic.

The Gulf Stream is one of the most important currents in this regard, since it gathers all of its water from the warm tropical waters of the Caribbean and the Gulf of Mexico.

As such, it keeps sea surface temperatures warm, causing the areas around it to be warm and more hospitable. Florida and much of the Southeastern United States, for instance, is mild all year round.

The warm waters from the Gulf Stream warms the winds, which then affect the weather on land.

The greatest impact the Gulf Stream has is on the climate found in Europe.

After it crosses the Atlantic Ocean, the Gulf stream splits into two parts.

One part heads north. We call this the North Atlantic Drift. The 2 nd part circulates down to West Africa.

Since it flows into the North Atlantic Drift, it too is warmed and it is believed that it helps keep places like Ireland and England much warmer than they would otherwise be at such a high latitude.

The Gulf Stream moderates weather along the eastern seaboard, warming the air and land there during the cooler months.

As well as keeping many places mild, the Gulf Stream’s warm sea surface temperatures also aid in the formation and strengthening of many of the hurricanes that move through the Gulf of Mexico.hurricanes

Let’s watch a video to learn more about the gulf stream. m-zO8L66uyg

The Gulf Stream was a big interest to sailors. They noticed how much faster sailing vessels could cross the Atlantic Ocean from the United States to Europe than sailing vessels crossing from Europe to the United States. That is thanks to the Gulf Stream.

We know energy is redistributed globally through water currents (such as the Gulf Stream). It is also redistributed through air currents(such as the jet stream).

Jet streams are fast moving ribbons of air high up in the atmosphere. They have a powerful influence on the weather conditions.

They are responsible for moving high and low air pressure systems.

They affect precipitation and temperatures. With the polar jet stream which crosses over the United States, colder air masses stay north of the jet stream.

Warmer air masses stay south of the jet stream. The jet stream separates the two.

The jet stream flows from the west to the east and changes location depending on global conditions.

weohIh_Bw weohIh_Bw Let’s watch a video to learn more about jet streams.

MWwx7Cll4 MWwx7Cll4 Here is another video about jet streams.

The location of the jet stream is extremely important for air travel. Not only does it cut time off a flight, it also creates fuel savings for the airline industry.

Within North America, the time needed to fly east across the continent can be decreased by about 30 minutes if an airplane can fly with the jet stream, or increased by more than that amount if it must fly west against it. continentminutesairplane

Let’s review what we have learned about water currents and jet streams. Answer the attached questions on the worksheet entitled L#25 How do global weather patterns affect local weather patterns..

In our next lesson we will continue to look at how global weather patterns affect local weather. We will also discuss hurricanes.

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