The stick (also referred to as a pusher) for underwater hockey is relatively short compared to that for field/ice/roller hockey, and should be coloured either white or black in its entirety to indicate the player’s team. The shape of the stick can affect playing style and is often a very personal choice.

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Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records.

Known to scientists as “tipping events,” they could contribute to mass extinction of species, dramatic sea level rise, extensive droughts and the transformation of forests into vast grasslands – among other upheavals our stressed world can ill afford.

This method of generating random data is called Monte Carlo analysis, after the famous casino, and it is widely used in statistical analysis to test procedures. When McIntyre and McKitrick fed these random data into the Mann procedure, out popped a hockey stick shape!

Irish physicist John Tyndall is commonly credited with discovering the greenhouse effect, which underpins the science of climate change. Starting in 1859, he published a series of studies on the way greenhouse gases including carbon dioxide trapped heat in the Earth’s atmosphere.

Electricity and Heat Production (25% of 2010 global greenhouse gas emissions): The burning of coal, natural gas, and oil for electricity and heat is the largest single source of global greenhouse gas emissions.

During the 1970s, the greenhouse effect became a major topic in many overlapping fields. Scientists eventually determined that a bit over half of the effect of humans on climate change is due to emissions of CO2 (mainly from fossil fuels but also from deforestation and cement manufacture).

infrared radiation

Oxygen and nitrogen are not greenhouse gases, because they are transparent to infrared light. These molecules are invisible because when you stretch one, it doesn’t change the electric field. In general, symmetrical molecules with only two atoms are not greenhouse gases.

Ozone

Ozone occurs in two layers of the atmosphere. The layer closest to the Earth’s surface is the troposphere. Here, ground- level or “bad” ozone is an air pollutant that is harmful to breathe and it damages crops, trees and other vegetation. It is a main ingredient of urban smog.

To balance this input of solar radiation, the Earth itself emits radiation to space. Some of this terrestrial radiation is trapped by greenhouse gases and radiated back to the Earth, resulting in the warming of the surface known as the greenhouse effect.

The portion of the natural background radiation that is emitted by naturally occurring radioactive materials, such as uranium, thorium, and radon in the earth.

Approximately 99% of solar, or shortwave, radiation at the earth’s surface is contained in the region from 0.3 to 3.0 µm while most of terrestrial, or longwave, radiation is contained in the region from 3.5 to 50 µm. Outside the earth’s atmosphere, solar radiation has an intensity of approximately 1370 watts/meter2.

Electromagnetic radiation emitted by the Earth’s surface and atmosphere is called terrestrial or longwave radiation (the latter being the preference of the World Meteorological Organization). The spectral distribution of emission from the Earth’s surface generally approximates that from a black body.

Terrestrial external radiation is due to the decay of radioactive materials in the earth itself. Terrestrial external radiation is created by the process of the natural breakdown—or radioactive decay—of radioisotopes in natural materials such as rocks, soil, vegetation, and groundwater.

This process is known as terrestrial radiation. The long wave radiation is absorbed by the atmospheric gases particularly by carbon dioxide and the other green house gases. Thus, the atmosphere is indirectly heated by the earth’s radiation. The atmosphere in turn radiates and transmits heat to the space.

In order, the most abundant greenhouse gases in Earth’s atmosphere are:

• Water vapor (H. 2O)
• Carbon dioxide (CO.
• Methane (CH.
• Nitrous oxide (N. 2O)
• Ozone (O.
• Chlorofluorocarbons (CFCs)
• Hydrofluorocarbons (includes HCFCs and HFCs)

Conduction, radiation and convection all play a role in moving heat between Earth’s surface and the atmosphere. Conduction directly affects air temperature only a few centimeters into the atmosphere. During the day, sunlight heats the ground, which in turn heats the air directly above it via conduction.

[more on electromagnetic radiation] It is infrared radiation that produce the warm feeling on our bodies. Most of the solar radiation is absorbed by the atmosphere and much of what reaches the earth’s surface is radiated back into the atmosphere to become heat energy.

The Earth does not continue to get hotter and hotter as it absorbs energy from the sun, because it gives off energy to space as invisible infrared radiation. The average Earth temperature required for energy balance with the sun would be a frigid –18 °C (0 °F), if there were no atmospheric greenhouse effect.