QUESTION = Why is a 1 degree temperature difference in climate such a big deal? GENERATION = The average temperature of the planet is about 37°C, so if it's only a 1 degree difference, that's going to be a pretty big deal. It's going to be the beginning of the end of the world, and that's a big deal for people living in coastal cities, because the temperature will rise significantly and that's going to have an impact on their daily life. The average global temperature is more than 37°C, so that's going to be a pretty big deal for people living in deserts, because the average global temperature will rise significantly and that's going to have an impact on their daily life. If the average global temperature is 1 degree difference, then that's going to be a very small difference. It's going to be a very small change in the climate, and it's going to have an impact on people living in deserts, because the average global temperature will rise significantly and that's going to have an impact on their daily life. The average global temperature is 2 degrees difference, so that's going to be a very large difference in the climate. RETRIEVAL #0 = Global warming controversy---over the existence of global warming debate has moved to further controversial issues, including: BULLET::::1. The social and environmental impacts BULLET::::2. The appropriate response to climate change BULLET::::3. Whether decisions require less uncertainty The single largest issue is the importance of a few degrees rise in temperature: Most people say, "A few degrees? So what? If I change my thermostat a few degrees, I'll live fine." ... [The] point is that one or two degrees is about the experience that we have had in the last 10,000 years, the era of human civilization. There haven't been—globally averaged, we're talking—fluctuations of more than a degree or so. So we're actually getting into uncharted territory from the point of view of the relatively benign climate of the last 10,000 years, if we warm up more than a degree or two. (Stephen H. Schneider) The other point that leads to major controversy—because it could have significant economic impacts—is whether action (usually, restrictions on the use of fossil fuels to reduce carbon-dioxide emissions) should be taken now, or in the near future; and whether those restrictions would have any meaningful effect on global temperature. Because of the economic ramifications of such restrictions, there are those, including RETRIEVAL #1 = Orders of magnitude (temperature)---Orders of magnitude (temperature) Section::::Detailed list for 100 K to 1000 K. Most ordinary human activity takes place at temperatures of this order of magnitude. Circumstances where water naturally occurs in liquid form are shown in light grey. Section::::External links. BULLET::::- Online Temperature Conversion RETRIEVAL #2 = Reasons for concern---studies assessed by Smith "et al." (2001) projected increasing net losses in world GDP for higher temperatures. More recent studies assessed by Schneider "et al." (2007) were consistent with these findings. Section::::Risk of irreversible large-scale and abrupt transitions. Systems may respond in an irregular, discontinuous, abrupt, and unpredictable way to climate change (Smith "et al.", 2001). This may apply to physical, biological and human systems. Available records of climate variability, for example, reveal sudden fluctuations of key variables at all time scales. Some changes in systems may be "irreversible." Some irreversible changes may be reversible over long time periods, for example, the partial melting of the Greenland ice sheet (IPCC, 2001d:93). Other changes may be intrinsically irreversible, for example, the extinction of species. Sometimes the word "singularity" is used to describe a system that behaves in an irregular and unpredictable way. Singularities could lead to rapid, large, and unexpected climate change impacts on local, regional, and global scales (Smith "et al.", 2001). Anticipating and adapting to such events and their impacts would be much more difficult than responding to "smooth" climate change. Examples of large-scale singularities include: BULLET:::: RETRIEVAL #3 = Nature---currents are another important factor in determining climate, particularly the major underwater thermohaline circulation which distributes heat energy from the equatorial oceans to the polar regions. These currents help to moderate the differences in temperature between winter and summer in the temperate zones. Also, without the redistributions of heat energy by the ocean currents and atmosphere, the tropics would be much hotter, and the polar regions much colder. Weather can have both beneficial and harmful effects. Extremes in weather, such as tornadoes or hurricanes and cyclones, can expend large amounts of energy along their paths, and produce devastation. Surface vegetation has evolved a dependence on the seasonal variation of the weather, and sudden changes lasting only a few years can have a dramatic effect, both on the vegetation and on the animals which depend on its growth for their food. Climate is a measure of the long-term trends in the weather. Various factors are known to influence the climate, including ocean currents, surface albedo, greenhouse gases, variations in the solar luminosity, and changes to the Earth's orbit. Based on historical records, the Earth is known to have undergone drastic climate changes in the past, including ice ages. The climate of a region depends on a number of factors, especially latitude. A latitudinal band of the surface with similar climatic attributes forms a climate region. There are a number of such RETRIEVAL #4 = Homogenization (climate)---forecasting, agriculture and hydrology. Moreover, the typical size of the breaks is often of the same order as the climatic change signal during the 20th century. Inhomogeneities are thus a significant source of uncertainty for the estimation of secular trends and decadal-scale variability. If all inhomogeneities would be purely random perturbations of the climate records, collectively their effect on the mean global climate signal would be negligible. However, certain changes are typical for certain periods and occurred in many stations, these are the most important causes as they can collectively lead to artificial biases in climate trends across large regions. Section::::Causes of inhomogeneities. The best known inhomogeneity is the urban heat island effect. The temperature in cities can be warmer than in the surrounding country side, especially at night. Thus as cities grow, one may expect that temperatures measured in cities become higher. On the other hand, with the advent of aviation, many meteorological offices and thus their stations have often been relocated from cities to nearby, typically cooler, airports. Other non-climatic changes can be caused by changes in measurement methods. Meteorological instruments are typically installed in a screen to protect them from direct sun and wetting. In the 19th century it was common to use a metal screen in front of a window on a North facing wall. However, the building may warm the RETRIEVAL #5 = Fahrenheit---quotes Celsius first, followed by Fahrenheit in brackets, "The Daily Telegraph" does not mention Fahrenheit on its daily weather page while "The Times" also has an all-metric daily weather page but has a Celsius-to-Fahrenheit conversion table. When publishing news stories, much of the UK press have adopted a tendency of using degrees Celsius in headlines and discussion relating to low temperatures and Fahrenheit for high temperatures. In February 2006, the writer of an article in "The Times" suggested that the rationale was one of emphasis: "−6 °C" sounds colder than "21 °F" and "94 °F" sounds more impressive than "34 °C". Section::::Unicode representation of symbol. Unicode provides the Fahrenheit symbol at code point . However, this is a compatibility character encoded for roundtrip compatibility with legacy encodings. The Unicode standard explicitly discourages the use of this character: "The sequence + is preferred over , and those two sequences should be treated as identical for searching." Section::::See also. BULLET::::- Comparison of temperature scales BULLET::::- Degree of frost Section::::External links. BULLET::::- Daniel Gabriel Fahrenheit (Polish-born Dutch physicist) – Encyclopædia Britannica BULLET::::- "At Auction | RETRIEVAL #6 = Heating degree day---number of electrical appliances running (e.g. computers raise their surrounding temperature) the amount of wind outside, and what temperature the occupants find comfortable. Another important factor is the amount of relative humidity indoors; this is important in determining how comfortable an individual will be. Other variables such as precipitation, cloud cover, heat index, building albedo, and snow cover can also alter a building's thermal response. Another problem with HDD is that care needs to be taken if they are to be used to compare climates internationally, because of the different baseline temperatures used as standard in different countries and the use of the Fahrenheit scale in the US and the Celsius scale almost everywhere else. This is further compounded by the use of different approximation methods in different countries. Section::::Conversion. To convert °F HDD to °C HDD: To convert °C HDD to °F HDD: Note that, because HDD are relative to a base temperature (as opposed to being relative to zero), it is incorrect to add or subtract 32 when converting degree days from Celsius to Fahrenheit or vice versa. Section::::See also. BULLET::::- Degree day BULLET::::- Heating, ventilation, and air conditioning BULLET::::- Sol