Oh, winds are not climate. Thanks for the clarification.
(S-1B) Global Climate, Global Wind Flow
Index
24b. Rotating Frames
The Sun
S-1. Sunlight & Earth
S-1A. Weather
S-1B. Global Climate
S-2.Solar Layers
S-3.The Magnetic Sun
S-3A. Interplanetary
Magnetic Fields
S-4. Colors of Sunlight
S-4A.Color Expts.
S-5.Waves & Photons
Optional: Quantum Physics
Q1.Quantum Physics
Q2. Atoms
Q3. Energy Levels
Q4. Radiation from
Hot Objects
Q5.The Atomic Nucleus
and Bohr's Model
Q6. Expansion of
Bohr's Model
Climate and Latitude
The distribution of the Sun's heat over surface of Earth Sun's heat is quite uneven. Heating is most intense near the equator, where the Sun's rays come down steeply. Such sunlight, arriving at a steep angle, heats the ground much more effectively than light that slants, whose heating is spread out over a wider area (see "The angle of the Sun's rays").
Most of climate is dictated by the way that heating is distributed. It also depends on the tilt of the Earth's axis which gives us the seasons, and by the distribution of oceans, which store the Sun's heat and moderate the climate. Regions far from the ocean experience greater extremes of hot and cold weather, and may also be drier.
The warm tropical regions are traditionally the ones between latitudes 23.5° north and south, lines of latitude known as the "tropic of cancer" and the "tropic of capricorn." Anywhere in that region, which straddles the equator, at least one day exists in the year when the noontime Sun is directly overhead. And the polar regions are the regions poleward of the arctic circles (latitude 66.5°) where at least on one day in winter, the center of the Sun is below the horizon all day long. Those are the regions experiencing "polar night" in midwinter, and hardly any plants survive there. In mid-summer, polar days get very long, but with the Sun close to the horizon, its rays arrive at a shallow angle and their heating power is minimal.
The Sun's energy input is what drives climate, but the atmosphere also has an important role. Heat given to the ground does not stay where it is deposited. Sooner or later the warm ground radiates it away in the form of infra-red light. Those infra-red rays, in turn, do not travel far before being re-absorbed by greenhouse gases such as water vapor (see S-1 Sunlight and the Earth). Later those gas molecules again give up their heat, also as infra-red radiation, some of which reaches further upwards. By such a chain of absorption and re-emission heat gradually spreads, like sunlight in a fog, until some of it reaches levels from where it can be radiated to space, never to return.
The level where this happens is the beginning of a dry and stable atmospheric layer known as the stratosphere. The part of the atmosphere below that-- the region where weather takes place, more active and more humid--is called the troposphere, and the boundary between it and the stratosphere is the tropopause
Large-scale air flows near the equator
As heat diffuses through the layers of the atmosphere, it is also spread by atmospheric flows, by winds. In general
--All air flows are powered by the heat energy
given to the ground by the Sun.
--Air flows try to get rid of this heat as efficiently as possible.
--In general, heated air flows away from where it is heated
to where it can best send its heat back to space.
Most heat arrives in the tropics, but it can be re-radiated from the top of the atmosphere anywhere on Earth. Spreading it out allows a larger area of the atmosphere to participate in its return. This yields a more efficient disposal of heat, and that is what global atmospheric flows try to achieve. Warm air is transported towards the poles, cooled air returns equatorward.
Currently Earth experiences a growth in the "greenhouse effect"--the effect of gases like CO2 (carbon dioxide), methane, water vapor and ozone, which impedes the flow of heat from the ground where it is first absorbed, to the top of the atmosphere where it is radiated back to space.
Global flows, described below, help drive heated air from the equator towards the poles, spreading the area of heat return. When the transport of heat from the ground to the top layers is impeded by the "greenhouse effect," such flows may be driven to spread the area participating in heat return, making them extend further poleward. The result of such spreading could be the recently observed melting of polar sea ice (which threatens polar bears) and of glaciers in Greenland and in Antarctica.
But how does this happen?
The answer is complicated (and I thank Dr. Mark Schoeberl of NASA's Goddard Space Flight Center for helping me out). First of all, since the atmosphere is 3 dimensional one may well ask--are the dominant motions vertical or horizontal? Logic alone is an uncertain guide. It is much better to observe how nature does it, or (in recent years) use large computers to simulate the physics, reassuring us that the factors we hold responsible indeed combine to act this way.
Hadley cell circulation
It was Hadley in 1735 who proposed the motion was mainly vertical (see drawing above). If the Earth did not rotate, such a flow would be confined to a north-south plane. Hot air would rise near the equator and cool down at higher altitudes, while cooler air from off-equator regions would flow equatorward and take its place. http://www-spof.gsfc.nasa.gov/stargaze/Sweather2.htm
gbopp wrote:
bigred1cav wrote:
There is no climate change
gbopp wrote:
Another plus to having a RV. Emergency shelter.
You never know when you'll need it. Especially with the 'changing' weather patterns.
I said 'changing' weather patterns. Not climate change. :W
