The climate of an area is an expression of the characteristic weather events it experiences. This is a result of the areas latitude, altitude, rainfall, prevailing winds and hours of sunshine it experiences. In turn, this will affect what types of plants and animals are best suited to a location.
When we refer to weather, by contrast, it is what we actually experience at that particular point in time. In the Southern Hemisphere regions of mid latitude, there is a generally dominant north-westerly wind. This is due the Earth spinning in an easterly direction at a 23.5- degree angle. This combined with the air being heated at the equator, and rising and then sinking as it is pushed southwards, creating a dominant direction of air flow from a north-westerly direction.
Energy from the sun drives processes that create our climate. Heat travels through space to Earth in waves of electromagnetic radiation that pass this energy to molecules in our atmosphere. This causes these molecules to move faster and expand upwards. Once they rise they then cool down again (because the upper atmosphere is cooler) and sink down again. This creates circular convection currents within our atmosphere. Another result is as the gases in the atmosphere expand they decrease in pressure creating high pressure weather systems associated with warm weather.
Our atmosphere is a layer of gas molecules held around the Earth by the power of gravity. These gases are most dense in the first 12 kilometres of the atmosphere called the troposphere, but expand out as far as 10,000 km becoming increasingly sparse (less dense) until they are so few that we consider it to be space. Gases in the atmosphere are critically important for life processes on Earth, and are required for the two great cell processes (photosynthesis and respiration) that are responsible for creating biological molecules to act as food sources as to convert these molecules into energy that can be used by cells.
There are also predictable patterns in the Earth’s atmosphere due to the shape of Earth, the angle it spins on and its orbit around the sun. These phenomena create a predictable series of weather events we refer to as being the climate of a region. This describes what we wouldexpect the weather to be at different times of the year.
This air flow is most pronounced in spring when the Earth is moving in its orbit to a position where the Southern hemisphere is facing towards the Sun and day length is increasing. In winter the Southern hemisphere receives a lot less heating from the sun because it is tilted away from the Sun in its orbit. This reduces the flow of warm air from the equator and increases the flow of cool air from the Southern pole, resulting in a dominant Southerly wind at this time.
When we refer to weather, by contrast, it is what we actually experience at that particular point in time. In the Southern Hemisphere regions of mid latitude, there is a generally dominant north-westerly wind. This is due the Earth spinning in an easterly direction at a 23.5- degree angle. This combined with the air being heated at the equator, and rising and then sinking as it is pushed southwards, creating a dominant direction of air flow from a north-westerly direction.
Energy from the sun drives processes that create our climate. Heat travels through space to Earth in waves of electromagnetic radiation that pass this energy to molecules in our atmosphere. This causes these molecules to move faster and expand upwards. Once they rise they then cool down again (because the upper atmosphere is cooler) and sink down again. This creates circular convection currents within our atmosphere. Another result is as the gases in the atmosphere expand they decrease in pressure creating high pressure weather systems associated with warm weather.
Our atmosphere is a layer of gas molecules held around the Earth by the power of gravity. These gases are most dense in the first 12 kilometres of the atmosphere called the troposphere, but expand out as far as 10,000 km becoming increasingly sparse (less dense) until they are so few that we consider it to be space. Gases in the atmosphere are critically important for life processes on Earth, and are required for the two great cell processes (photosynthesis and respiration) that are responsible for creating biological molecules to act as food sources as to convert these molecules into energy that can be used by cells.
There are also predictable patterns in the Earth’s atmosphere due to the shape of Earth, the angle it spins on and its orbit around the sun. These phenomena create a predictable series of weather events we refer to as being the climate of a region. This describes what we wouldexpect the weather to be at different times of the year.
This air flow is most pronounced in spring when the Earth is moving in its orbit to a position where the Southern hemisphere is facing towards the Sun and day length is increasing. In winter the Southern hemisphere receives a lot less heating from the sun because it is tilted away from the Sun in its orbit. This reduces the flow of warm air from the equator and increases the flow of cool air from the Southern pole, resulting in a dominant Southerly wind at this time.
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Patterns in Atmosphere
The atmosphere also holds in heat close to the surface of the Earth without which it would be to impossible for life to exist on the surface of Earth due to it being too cold. The heat is trapped in a process called the greenhouse effect where gases in the atmosphere absorb and re-emit heat. This traps and spreads the heat in the atmosphere especially where the gases are most dense close to the surface of the Earth. In a similar way, we create glasshouses to trap heat. On Venus, the atmosphere is so dense that lead will melt on its surface, while on Mars so sparse that liquid water can’t flow on its surface.
Air will move between areas of different pressure systems in an effort to equalize the pressure between them. So, if you get a big high pressure system close to a big low pressure system it will cause a large storm to form due to the high-speed movement of air. Alternatively, the air will be very still in the middle of a large high pressure system because the air there is far away from areas of the atmosphere with different pressure systems.
The combination of these two mechanisms allows us to understand weather. If an area is heated by a lot by the sun the air there will expand creating high pressure systems and if an area does not receive a lot of sun it will create low pressure systems.
There are therefore two mechanism behind the movement of air in our atmosphere, the heating and expansion of air by the Sun causing it to rise and then cool down and sink again and the creation of areas of different pressures (high and low weather systems) .
This creates circular convection currents in the atmosphere (called cells) that in turn create predictable weather patterns at different times of the year. An areas location in context to these cells determines the yearly weather patterns it experiences. This is then further influenced by interactions of these air currents with landscape terrain.
Air will move between areas of different pressure systems in an effort to equalize the pressure between them. So, if you get a big high pressure system close to a big low pressure system it will cause a large storm to form due to the high-speed movement of air. Alternatively, the air will be very still in the middle of a large high pressure system because the air there is far away from areas of the atmosphere with different pressure systems.
The combination of these two mechanisms allows us to understand weather. If an area is heated by a lot by the sun the air there will expand creating high pressure systems and if an area does not receive a lot of sun it will create low pressure systems.
There are therefore two mechanism behind the movement of air in our atmosphere, the heating and expansion of air by the Sun causing it to rise and then cool down and sink again and the creation of areas of different pressures (high and low weather systems) .
This creates circular convection currents in the atmosphere (called cells) that in turn create predictable weather patterns at different times of the year. An areas location in context to these cells determines the yearly weather patterns it experiences. This is then further influenced by interactions of these air currents with landscape terrain.
Ocean Currents
Ocean currents can also impact upon the climate of a region. Similar to the pattern in the atmosphere, the oceans at the equator are heated and the water rises and is pushed outwards towards the poles where it cools and sinks again. This creates large circular convection currents that can flow quite strongly and are used by many marine creatures such as whales, eel and turtles to navigate large stretches of ocean.
The flow of these currents is modified by land forms, which sometime push them into regions further toward the poles than they would normally flow. This is responsible for countries such as England experiencing a warmer climate than they normally would because of the relatively warm ocean currents flowing along its cost.
Because water is more dense and heats more slowly than air, water also acts to moderate temperature changes. The result of this is if an area is closer to the ocean or another large body of water it heats up more slowly and also cools down more slowly.
This makes areas surrounded by large bodies of water more temperate - or less changeable in temperature. Areas of land of approximately 30 degrees latitude are considered the most temperate as they experience moderate year round temperatures and generally experience cool ocean temperatures that buffer against increases in temperature in summer.
The flow of these currents is modified by land forms, which sometime push them into regions further toward the poles than they would normally flow. This is responsible for countries such as England experiencing a warmer climate than they normally would because of the relatively warm ocean currents flowing along its cost.
Because water is more dense and heats more slowly than air, water also acts to moderate temperature changes. The result of this is if an area is closer to the ocean or another large body of water it heats up more slowly and also cools down more slowly.
This makes areas surrounded by large bodies of water more temperate - or less changeable in temperature. Areas of land of approximately 30 degrees latitude are considered the most temperate as they experience moderate year round temperatures and generally experience cool ocean temperatures that buffer against increases in temperature in summer.
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Climate Change
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