Climate change, global warming and greenhouse gases niwa q gastrobar


• Since the end of the last ice age (14,000 – 10,000 years ago) globally averaged surface temperatures have fluctuated over a range of up to 2°C on time scales of centuries or more. Factors influencing these changes probably included fluctuations in the radiation output from the sun, and changes in circulation and overturning in the oceans.

• glaciers: Variations in the past size of glaciers can be inferred from the location of moraines (rocks and debris deposited by glaciers) and buried soils, and in the presence of glacial features in the landscape. In New Zealand, cool summer temperatures are only one factor in promoting ice accumulation on glaciers, and snow accumulation rates also respond to changes in the strength and direction of the westerly wind flow and sea level pressure in summer.

• boreholes: It is sometimes possible to deduce past surface temperatures going back several hundred years by measuring the way temperature varies with depth in a borehole several hundred metres deep (at a suitable site not disturbed by groundwater flow). This is because fluctuations in ground surface temperatures propagate slowly downwards into the earth as a "temperature wave".

• instrumental Measurements and written or oral records: In New Zealand, quantitative records of temperature and other meteorological records are available only for the past 150 years. gas bloating Such records must be analysed carefully, to identify the influence of any non-climate factors (such as changes in observing site or method, or encroaching urban development).

There are likely to be more severe droughts and/or floods in some places, and less severe droughts and/or floods in others. Some models suggest a possibility of more extreme (i.e. high) rainfall events. It is not yet possible to predict whether changes are likely in the occurrence or geographical distribution of severe storms, such as tropical cyclones.

Greenhouse gases warm the atmosphere by absorbing some of the thermal radiation emitted from the Earth’s surface. Incoming solar radiation is transmitted through the atmosphere to the Earth’s surface. wireless electricity how it works The energy is retransmitted by the Earth’s surface as thermal radiation. Some of the thermal radiation is absorbed by the greenhouse gases instead of being retransmitted out to space, and so there is a warming of the atmosphere. The important greenhouse gases which are directly influenced by human activities are carbon dioxide (CO 2), methane (CH 4), nitrous oxide (N 2O), chlorofluorocarbons (CFCs) and ozone. Water vapour is also an important greenhouse gas. Are they changing in the atmosphere?

The concentrations of greenhouse gases in the atmosphere are increasing due to human activities. a gas is compressed at a constant pressure of The Industrial Revolution has resulted in an increase in the concentration of CO 2 in the atmosphere of about 30%, from 280 ppmv around the year 1700 to a value of over 360 ppmv at the present day. Accurate measurements of CO 2 have been made in New Zealand at Baring Head since 1971. Data from ice cores show that during the 17th and 18th centuries the CH 4 concentration in the atmosphere was about 0.7 ppmv. The current CH4 concentration is more than double that value, approximately 1770 ppb. gas bubbler Do we know why?

The increasing concentration of CO2 is caused by the burning of fossil fuels (such as oil, gas and coal), and the destruction of forests. These activities release large amounts of CO2 into the atmosphere. The main natural source of CH4 is from wetlands. A variety of other sources of CH4 result directly or indirectly from human activities, for example from ruminant animals, rice paddies, leakage from natural gas pipelines, and from the decay of rubbish in landfill sites. However, CH4 growth rates have declined since the 1990s, potentially due to reduced gas pipeline leaks and the drying of wetlands. Why do we expect climate to change?

• Global mean surface temperature increased by 0.74°C between 1906 and 2005, a change which is unlikely to be entirely natural in origin. The balance of evidence suggests a discernible human influence on global climate. Much of the 1.8±0.5 mm yr-1 average global sea level rise between 1961 and 2003 may be related to the rise in global temperature.

Energy emitted from the sun ("solar radiation") is concentrated in a region of short wavelengths including visible light. n gas price Much of the short wave solar radiation travels down through the Earth’s atmosphere to the surface virtually unimpeded. origin electricity account Some of the solar radiation is reflected straight back into space by clouds and by the earth’s surface. Much of the solar radiation is absorbed at the earth’s surface, causing the surface and the lower parts of the atmosphere to warm.

The presence of greenhouse gases in the atmosphere, however, changes the radiation balance. Heat radiation (infra-red) emitted by the Earth is concentrated at long wavelengths and is strongly absorbed by greenhouse gases in the atmosphere, such as water vapour, carbon dioxide and methane. As a result, the surface temperature of the globe is around 15°C on average, 33°C warmer than it would be if there was no atmosphere. This is called the natural greenhouse effect. What is the enhanced greenhouse effect?

If extra amounts of greenhouse gases are added to the atmosphere, such as from human activities, then they will absorb more of the infra-red radiation. The Earth’s surface and the lower atmosphere will warm further until a balance of incoming and outgoing radiation is reached again (the emission of infra-red radiation increases as the temperature of the emitting body rises). This extra warming is called the enhanced greenhouse effect. How does methane gas from cows damage our environment?

Methane is a so-called greenhouse gas. Greenhouse gases impact the environment through warming the atmosphere. The concentration of greenhouse gases has risen significantly in the past 200 years, in part due to human activities. static electricity vocabulary words One of the biggest contributors to the atmospheric methane concentration is farmed livestock, especially cattle and sheep. These animals produce methane naturally as part of their digestive process, and belch it, especially while ‘chewing the cud’. As the human population has grown, the number of farmed animals has increased markedly to meet the human demand for food through meat and dairy products. NIWA Greenhouse Gas Measurements