Rain shadow

Regional climate should be the first consideration when evaluating the suitability of an alternative landfill cover for a site. If the regional climate appears to be compatible with the requirements of the alternative cover, then site characteristics should be examined to determine whether the site climate is also suitable. Site and regional climate may differ substantially for sites near mountains, in valleys, in the rain shadow of coastal mountains, or near the coast. The Air Force Center for Environmental Excellence commissioned a generic assessment of the suitability of the ET landfill cover based on regional climate for the continental United States.4... 

Most deserts and (semi-) arid regions occur between 10° and 35° latitude (e g. Sahara desert, Kalahari desert), in the interior parts of continents (e g. Australia, Gobi desert) and in rain shadow areas in fold belts (e.g. Peru, Nepal). Large parts of the arctic tundra receive less than 250 mm precipitation per annum and qualify as arid regions too (FAO, 2001). 

South America has two major areas, separated by the Andes Mountain ridges, where arid and semi-arid zones dominate. In the barren, coastal Atacama desert of Peru and northern Chile, precipitation is extremely limited and comes as winter mists or drizzles. In the rain shadow east of the Andes in Argentina, arid zones are widespread. South America apparently has only a slightly greater proportion of dry zones than North America. 

Plant type can determine water requirements. Drought-resistant plants, adapted to surviving extremely dry conditions, positively thrive where water is short, and may fail if the soil is too wet. The location of the plant also has a bearing on its watering requirements. Plants in containers, for example, rely on you, the gardener, for their supply. Plants in "rain-shadow" locations—such as next to a house, wall or fence, where the soil is sheltered and thus receives less rain—are more likely to be short of water. 

Planting climbers Put any support system, such as stretched horizontal wires, in place before planting the climber. To avoid siting it in a "rain shadow," plant it a little distance away from a wall or fence, guiding the stems of the plant in with canes. 

The Owens Valley lies in east central California between the Sierra Nevadas to the west and the Inyo-White Mountains to the east. The valley is 120 miles long, but only seventeen miles across at its widest point. While the valley floor lies at an elevation of approximately 4,000 feet, the mountains on either side tower to 12-14,000 feet. This topography is important for two reasons. First, the Sierra Nevadas create a rain shadow... 

Aridity is of interest in paleoelevation reconstruction for two reasons (1) in extreme aridity cases, the 818Osc values are dominated by evaporation, and realistic estimates of paleoelevation are probably not obtainable, no matter the sampling density, and (2) aridity develops in rain shadows, and thus may provide qualitative evidence of orogenic blockage of moisture. 

APPLICATIONS OF STABLE ISOTOPE PALEOALTIMETRY Tracking of orogenic rain shadows... 

Figure 6. Topography (solid), precipitation (gray), and 8180 and 8D values along a transect across the southern South Island of New Zealand. The modern Southern Alps create a strong rain shadow on the eastern side of the mountain range that is characterized by a reduction in rainfall from up to 3000 mm/a on the western side to values <300 mm/a on the eastern side of the range. Similarly, hydrogen and oxygen isotopic compositions of meteoric water are strongly depleted in D and 180, and decrease by ca. —40%o and -4.5%o, respectively. Circles SlsO values, diamonds 8D values. Data from Chamberlain et al. (1999) and Stewart et al. (1983). After Chamberlain et al. (1999).

Other studies of isotopic rain shadows in the Washington Cascades (Takeuchi and Larson 2005) and the Sierra Nevada of California (Chamberlain and Poage 2000 Poage and Chamber-lain 2002) used smectite in paleosols and altered ashes as an isotopic proxy. In these studies, the oxygen isotope composition of smectite from east of the Washington Cascades decreased by 3 to 4%o from the middle Miocene to recent, whereas smectite from east of the Sierra Nevada increased by 2 to 3%o from the middle Miocene to late Pliocene. The two studies argued that these isotopic results indicate an elevation increase in the Washington Cascades (Takeuchi and Larson... 

Koch PL, Crowley BE (2005) The isotopic rain shadow and elevation history of the Sierra Nevada Mountains, California. Eos Transactions Am Geophys Union 86(52), Fall Meeting Suppl... 

Poage MA, Chamberlain CP (2002) Stable isotopic evidence for a Pre-Middle Miocene rain shadow in the western Basin and Range Implications for the paleotopogaphy of the Sierra Nevada. Tectonics 21 16-1 -16-10... 

Takeuchi A, Larson PB (2005) Oxygen isotope evidence for the late Cenozoic development of an orographic rain shadow in eastern Washington. Geology 223 127-146... 

The Research Unit lies within the rain shadow of the Cascade Mountains of Washington. The average yearly rainfall of the area is 9.00 inches, only about 8% of which falls from mid-June to mid-September. During the same 3 months the rate of evaporation is three times as great as the average annual rainfall. Because of this and the low intensity of the rainfall, surface runoff occurs only from the shallow layer above the frost line. 

Vaks, A., Bar-Matthews, M., Ayalon, A., Schilman, B., Gilmour, M., Hawkes-worth, C.J., Frumkin, A., Kaufman, A. Matthews, A. (2003) Paleoclimate reconstruction based on the timing of speleothem growth and oxygen and carbon isotope composition in a cave located in the rain shadow in Israel. Quaternary Research 59, 182-193. 

Because of the ready solubility of sodium nitrate, it has been argued that it exists to such an extent in the Atacama as it is drier than any of the other deserts in the world. Sub-tropical subsiding air, the upwelling of cold offshore waters, and the rain-shadow effect of the Andes, create this aridity. The most intense aridity occurs in northern Chile, which receives less than 10 mm of rainfall per annum. Indeed, some stations, such as Calama, receive on average less than 2 mm. The climate station at Quillagua (mean annual rainfall 0.05 mm) can lay claim to be the driest place on Earth (Middleton, 2001). 

Because light levels (which control temperature, total productivity and the duration of seasonal growth outside the tropics) and rainfall exhibit latitudinal variations (Fig. 3.12), it is not surprising that the distribution of the major higher plant associations on land (biomes) are arranged in broadly latitudinal belts, as shown in Fig. 3.13.The general trends are modified by factors such as altitude, mountain rain-shadows and the thermal influ-... 

Stable isotopes of bioapatites can be used to investigate tectonics via a paleoclimate link. One direct climate-tectonics link is the generation of rain shadows by mountain ranges (Kohn et al. 2003). Mountain ranges in western North America profoundly affect isotope compositions of meteoric water. The N-S trending Sierra Nevada, Cascades, and... 

Ashwill M (1983) Seven fossil floras in the rain shadow of the Cascade Moimtains, Oregon. Oregon Geology 45 107-111... 

The distribution of IDD reflects the geochemistry of iodine with large areas of iodine deficiency. These occur in central regions, and mountainous and rain shadow areas. Middlesbrough is less than 20 km from the sea and would therefore not be expected to be iodine deficient. However, the data from our study suggests that this is not the case for both pregnant and non-pregnant women. 

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