Poles south

The discovery of ozone holes over Antarctica in the mid-1980s was strong observational evidence to support the Rowland and Molina hypothesis. The atmosphere over the south pole is complex because of the long periods of total darkness and sunlight and the presence of a polar vortex and polar stratospheric clouds. However, researchers have found evidence to support the role of CIO in the rapid depletion of stratospheric ozone over the south pole. Figure 11-3 shows the profile of ozone and CIO measured at an altitude of 18 km on an aircraft flight from southern Chile toward the south pole on September 21, 1987. One month earlier the ozone levels were fairly uniform around 2 ppm (vol). 

The catalytic cycle described earlier (reactions 8 and 9) cannot explain the rapid depletion of ozone over the South Pole, because reaction 9 requires free oxygen atoms, which are too scarce in the polar stratosphere to react at any appreciable rate with QO. Several catalytic cycles that do not require oxygen atoms have been suggested as being at work over Antarctica. 

A recent development that has substantially raised our knowledge about the carbon cycle is the measurement of the O2/N2 atmospheric ratio (Heimann, 1997). Figure 11-3 shows the combined curves of CO2 for Mauna Loa and South Pole as well as the recent development of data regarding the oxygen to nitrogen ratio in... 

Fig. 11-3 Direct atmospheric measurements of the CO2 concentration (left-hand scale) at Mauna Loa (Hawaii) and the South Pole station (Keeling et al., 1995) together with the concurrently observed decrease in atmospheric oxygen content (right-hand scale) at La Jolla, CA after 1989. (Taken from Heimann (1997) with permission from the Royal Swedish Academy of Sciences.)...

The atmospheric CO2 content increased by about 1 ppmv per year during the period 1959-1978 (Bacastow and Keeling, 1981) with the South Pole Pco increase lagging somewhat behind the Mauna Loa (19.5°N,155.6 "W) data. This difference is consistent with our knowledge of interhemispheric mixing times and the fact that most fossil fuel emissions occur in the northern hemisphere (see also Conway et al, 1994a). 

Due to the imbalance of sources and sinks, atmospheric N2O is increasing by 3 Tg N/yr or 0.2%/yr. Figure 12-9 shows average N2O mixing ratios from four stations in the NOAA-CMDL network, Barrow, Mauna Loa, Samoa, and the South Pole (data are from the NOAA-CMDL and can be obtained from www.cmdl.noaa.gov). The most recent IPCC estimate gives a total N2O source of 16 Tg N, 7 Tg of which are a result of human activities (IPCC, 1997). The largest contribution to the anthropogenic N2O sources is 3 Tg N from... 

I Byrd J Siple Dome K South Pole L Taylor Dome M Vostok N DomeC 0 Law Dome... 

O DE08 Ice Core + South Pole Flask Data... 

Fig. 18-11 Records of atmospheric CO2 in Antarctica for the past 1000 years. Open circles are ice-core data from Law Dome, on the coast of east Antarctica (Etheridge et al., 1996). Plus signs are direct measurements of CO2 in air samples collected monthly at the South Pole (NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, Colorado).

Fig. 18-17 Ice core records of N2O. (a) Data of Machida et al. (1995) from the H15 ice core, east Antarctica, for the time period 1750-1950, and monthly atmospheric N2O measurements at the South Pole from the NOAA Climate and Diagnostics Laboratory, Boulder, CO, for the period 1989-1998. (b) Data from Leuenberger and Siegenthaler (1992) from the Byrd ice core in West Antarctica.

Battle, M., Bender, M., Dowers, T. et al. (1996). Atmospheric gas concentrations over the past century measured in air from fim at the South Pole. Nature 383,231-235. 

Thus therefore you see the opposite poles of the litde world to concur in effect, and that in all respects, with that great world, counting the South pole form the Aequinoctiall. For if we divide the Load-stone in the middle, that part in the Aequinoctiall which is next the north pole will serve and stand in place of the South pole ... 

C05-0130. In 1990, carbon dioxide levels at the South Pole reached 351.5 parts per million by volume. (The 1958 reading was 314.6 ppm by volume.) Convert this reading to a partial pressure in atmospheres. At this level, how many CO2 molecules are there in 1.0 L of dry air at -45 °C ... 

The aurora borealis, a spectacular atmospheric light show shown in Figure 7-25. originates in the thermosphere. In addition to electromagnetic radiation, the sun emits a steady stream of protons and electrons. The Earth s magnetic field deflects most of these particles, but some reach the thermosphere above the north and south poles of the... 

The extensive layered sediments at the south pole, which contain water ice, will provide information on climatic variations. The subsurface sounding radar instrument SHARAD (Shallow Radar) on board the Mars Reconnaissance Orbiter carried out a detailed cartographic study of the subsurface at the Martian south pole. The data indicate that the sediments there have been subjected to considerable erosion (R. Seu et al 2007). The density of the material deposited at the Martian south pole was calculated by M. T. Zuber and co-workers by combining data from the gravitational field with those from various instruments on board the Mars Orbiter, they obtained a value of 1,200 kg/m3. This value corresponds to that calculated for water ice containing about 15% dust (Zuber et al 2007). 

The layers of sediment at the Martian south pole do not consist of pure ice they are interspersed by layers of dust. The latest data were obtained by the Mars Advanced Radar for Subsurface and Ionospheric Sounding apparatus (MARSIS) on board the Mars Express Orbiter. The radar waves from the instrument pass through the ice layers until they reach the base layer, which can be at a depth of up to 3.7 km. The distribution of the ice at the south pole is asymmetric, and its total volume has been estimated to be 1.6 x 106km3 this corresponds to an amount of water which would cover the whole planet with a layer 11 metres deep (Plaut et al., 2007). 

The Miocene land distribution is compared with the present land distribution in Figure 7-24. There has been an increase in land fraction at the South Pole since the Miocene, a decrease in middle latitudes in the South-... 

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