Climatic variable

Anthropogenic Emissions and Climate Variability. Journal of Geophysical Research 103(DI 3) 15979-15993. Fkickinger, J., ct al. (1999). Variations in Atmospheric NjO Concentration During Abrupt Climate Changes. Science 285 227-230. 

Climatic change may occur as fluctuations in means and/or extremes of climatic variables. Most studies of climatic change, however, focus almost exclusively on trends in mean values of climatic variables (usually temperature). In fact, a climatic shift also may be manifest as an increase or decrease in the frequency of occurrence of extremes. That is, episodes of drought or excessive rainfall or record high or low temperatures may become more or less frequent. Changes in frequency of extremes may occur with little or no concurrent change in means. 

The concept of global radiative equilibrium is useful in identifying the various factors that govern climatic variability. At radiative equilibrium, the flux of solar radiation absorbed by the planet equals the flux of infrared radiation to space. That is. 

Figure 1. Both internal (white arrows) and external (black arrows) processes influence climatic variability. (Reproduced with permission from ref. 30. Copyright 1975 National Academy Press, National Academy of Sciences.)...

On the structure and evolution of ENSO-related climate variability in the tropical Pacific Lessons from TOGA. /. Geophys. Res. 102, 14,241-14,259. 

Goulden, M. L., Munger, J. W., Pan, S.-M., Daube, B. C. and Wofsy, S. C. (1996). Exchange of carbon dioxide by a deciduous forest Response to inter-armual climate variability. Science 271,1576-1578. 

Heimann, M. and Keeling, C. D. (1989). A three-dimensional model of atmospheric CO2 transport based on observed winds 2. Model description and simulated tracer experiments. In "Aspects of Climate Variability in the Pacific and Western Americas," Geophys. Monogr. Ser. vol. 55 (D. H. Peterson, ed.), pp. 237-275, AGU, Washington, DC. 

Most climate variability will occur with 20 and 40 kyr periods. 

Consequences of Climate Variability and Human Water Demand on Freshwater Ecosystems A Mediterranean Perspective from the United States... 

Climate Variability, Climate Change, and Climate Adaptation. 67... 

The area of California influenced by a Mediterranean climate is home to over 30 million people. Climate variability and human water demand make freshwater a very precious resource. Allocations of water to cities, agriculture, and the environment create continual tension as demands for this vital and over-allocated resource grow. This paper presents a brief overview of water resource science and policy in a Mediterranean climate with substantial challenges from climate variability, climate change, and increasing human need. 

The water supply to the Delta comes predominantly from the Sacramento River ( 80%) with lesser amounts from the San Joaquin River ( 15%) and rivers on the east side of the Delta ( 5%). Year-to-year variability in water supply is large. Combined average annual unimpaired runoff (an estimate of flows without upstream dams or diversions) for the Sacramento and San Joaquin rivers for the past century ranges from 6.2 km in 1977 to 68 km in 1983 [2]. The percentage of freshwater flows that go to San Francisco Bay are estimated to be 87% in wet years, 69% in average years, and 51% in dry years. Climate variability associated with the Mediterranean chmate of the region is an essential component of the Delta ecosystem. 

Greenough G, McGeehin M, Bernard SM et al (2001) The potential impacts of climate variability and change on health impacts of extreme weather events in the United States. Environ Health Perspect 109 191-198... 

Tieszen 1991). Water stress, for instance, lowers photo synthetic discrimination against C, resulting in isotopic enrichment. C4 plants are not affected isotopically by environmental parameters although their distributions are (Ehleringer et al. 1997). Under conditions of increasing aridity, the climate variable of most likely importance in African sites, C3 plants should become slightly more enriched on average. Therefore one should be cautious about use... 

Shackleton, N.J. 1995 New data on the evolution of Pliocene climatic variability. /nVrba, E.S., Denton, G.H., Partridge, T.C. and Burckle, L.H., eds., Paleoclimate and Evolution. New Haven, CT, Yale University Press 242-248. 

McDermott F, Mattey DP, Hawkesworth CJ (2001) Centennial-scale Holocene climate variability revealed by a high-resolntion speleotherm record from SW Ireland. Science 294 1328-1331 McGarry SF, Baker A (2000) Organic acid fluorescence applications to speleothem paleoenvironmental reconstraction. Qnat Sci Rev 19 1087-1101... 

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