High latitudes

Similar heterogeneous reactions also can occur, but somewhat less efticientiy, in the lower stratosphere on global sulfate clouds (ie, aerosols of sulfuric acid), which are formed by oxidation of SO2 and COS from volcanic and biological activity, respectively (80). The effect is most pronounced in the colder regions of the stratosphere at high latitudes. Indeed, the sulfate aerosols resulting from emptions of El Chicon in 1982 and Mt. Pinatubo in 1991 have been impHcated in subsequent reduced ozone concentrations (85). 

In addition to widely differing degrees of dependence on natural gas, different regional economies exhibit dramatically contrasting consumption patterns for the gas that they do consume. Strong distinctions are evident, for example, between the diversified and finely-tuned natural-gas markets of high-income, high-latitude countries in Europe and... 

Through much of its history. Earth s climate was much warmer than it is today, and temperatures decreased more slowly toward the poles. At other times. Earth was colder than it is today, and massive glaciers formed at high latitudes. We live in one of the colder periods of Earth s history. 

The simplest kind of gridpoint model is one where only one spatial dimension is considered, most often the vertical. Such one-dimensional models are particularly useful when the conditions are horizontally homogeneous and the main transport occurs in the vertical direction. Examples of such situations are the vertical distribution of CO2 within the ocean (except for the downwelling regions in high latitudes, Sie-genthaler, 1983) and the vertical distribution of... 

Because it depends on a number of conditions that are themselves inherently variable, runoff tends to vary even more than precipitation, particularly over time. Seasonal runoff patterns depend largely on latitude and altitude of the watershed, due to the importance of snowmelt in runoff peaks. In high-latitude basins or those with significant high-altitude contribut-... 

Latent heat is the energy associated with phase changes. Evaporation of water requires an energy input of 2.5 x 10 J per kilogram of water at 0°C, almost 600 times the specific heat. When water vapor is transported via atmospheric circulation and recondensed, latent heat energy is released at the new location. Atmospheric transport of water vapor thus transfers both latent and sensible heat from low to high latitudes. 

The horizontal isopycnal thermocline model is important for the problem of determining the fate of the excess atmospheric CO2. The increase of CO2 in the atmosphere is modulated by transport of excess CO2 from the atmosphere into the interior of the ocean. The direct ventilation of the thermocline in its outcropping regions at high latitudes plays an important... 

A requirement of the heat balance for a steady-state ocean is that the input of new cold abyssal water (Antarctic Bottom Water and North Atlantic Deep Water) sinking in the high-latitude regions must be balanced by input of... 

Over much of the ocean (exclusive of upwelling regions, high-latitude areas and specific high-nutrient, low-chlorophyll regions) the vertical distribution of dissolved POt is represented by the shape of the profile displayed in Fig. 14-6, which is similar to the shape observed for the... 

Tilt variations also do not affect the annual total of solar energy received by the whole Earth, but do change the annual total for polar regions (simultaneously for both hemispheres). Tilt also affects the seasonal insolation at high latitudes, with greater tilt leading to warmer summers and cooler winters in both hemispheres. 

---