Climate warming

Water vapor can be a climate warming force when it traps heat, or can cause either climate warming or cooling when it takes the form of clouds, which reflect incoming solar energy away from Earth. 

One such feedback is the influence of clouds and water vapor. As the climate warms, more water vapor enters the atmosphere. But how much And which parts of the atmosphere, high or low And how does the increased humidity affect cloud formation While the relationships among clouds, water vapor, and global climate are complicated in and of themselves, the situation is further complicated by the fact that aerosols exert a poorly understood influence on clouds. 

Some have also predicted a series of thirdhand impacts that might occur if the climate warms and becomes more dynamic. Wildlife populations would be affected (positively and negatively), as would some vegetative growth patterns. The home range of various animal and insect populations might shift, exposing people to diseases that were previously uncommon to their area, and so on. 

Extrapolation of this model calculation to the future climate warming suggests that an amplification of the current rate of increase in atmospheric CO2 content could result from climate-induced changes in ocean circulation rates. 

A positive feedback between vegetation and atmospheric CO2 will occur if biomass declines. This will happen to the extent that climatic warming causes increased water stress, either through decreased precipitation or increased evap-otransporation, particularly on soils of low water-holding capacity. Decreases in soil nutrient availability, either directly caused by drought or indirectly caused by replacement with taxa with more recalcitrant litter, may further decrease the net release of carbon from the biosphere to the atmosphere. Positive feedback will also arise if the current standing biomass of trees is replaced by small trees, shrubs, and herbs that store less carbon. 

Paleozoic Cambrian 600 Myr Climate warms, O2 levels approach current level most animal phyla present, including some that failed to survive algae and cyanobacteria diversify... 

Sarmiento, J. L., Hughes, T. M. C., Stouffer, R. J. and Manabe, S. (1998). Simulated response of the ocean carbon cycle to anthropogenic climate warming. Nature 393,245-249. 

Labat D, Godderis Y, Probst JL et al (2004) Evidence for global runoff increase related to climate warming. Adv Water Pollut Res 27 631-642... 

Another manifestation of climate warming can be seen in the timing and volume of spring runoff from the Sacramento River [4, 33]. River flows are peaking earlier in the year compared to the early twentieth century (about 3 weeks earlier on... 

Betts R, Cox P, Collins M, Harris P, Huntingford C, Jones D. The role of ecosystem-atmosphere interactions in simulated Amazonian precipitation decrease and forest dieback under global climate warming. Theoretical and Applied Climatology, 2004. 78(1) pp. 157-175. doi 10.1007/s00704-004-0050-y... 

The faster the climate warms up, the more likely it is that feedback processes will change the greenhouse gas buildup. There are many that believe that C02 and other trace greenhouse gases could double sometime within the next century. 

There is an effort to tighten estimates of how the Earth will respond to climate warming. The sensitivity of new climate models has improved, but to fully understand the Earth s response to climate warming, a better knowledge of clouds and aerosols is needed, as well as improved and more and better records of past climate changes and their drivers. 

Harvell CD, Mitchell CE, Ward JR, Altizer S, Dobson AP, Ostfeld RS, Samuel MD (2002) Ecology - climate warming and disease risks for terrestrial and marine biota. Science 296 2158-2162 Hauck P, Thilmony R, He SY (2003) A Pseudomonas syringae type III effector suppresses cell wall-based extracellular defense in susceptible Arabidopsis plants. Proc Natl Acad Sci USA 100 8577-8582... 

Base cations are mobilized by weathering and cation exchange reactions that neutralize acids in the watershed. They respond therefore indirectly to changes in sulphate and nitrate concentrations. In fact, if acid anion concentrations (mainly sulphate) decrease, base cations are also expected to decrease. However, in the last few years an increase of the occurrence of alkaline rain episodes (probably due to climatic effects) has been observed and it is likely that calcareous Saharan dust, rich in base cations, is responsible for it [27]. Accelerated weathering, resulting from recent climate warming may also contribute to higher base cation concentrations [28]. 

Because of decreased SO2 emissions, the importance of nitrogen for freshwater acidification becomes more and more determinant. Therefore, uncertainties in the evolution of nitrogen emissions make it difficult to predict future trends in freshwater recovery. On the other hand, climate warming may increase the number of alkaline rain episodes (containing Saharan dust) and enhance weathering reactions, which buffer better acid precipitation, increasing alkalinity and pH. 

Schindler, D. W., P. J. Curtis, B. R. Parker, and M. P. Stainton. 1996. Consequences of climate warming and lake acidification for UV-B penetration in North American boreal lakes. 

J. (2002). Plant community composition mediates both large transient decline and predicted long term recovery of soil carbon under climate warming. Global Biogechem. Cycles 16(4), 1055. 

Cai and Whetton (2002) drew attention to the fact that ocean dynamics can considerably aflfect future global-scale precipitation. Developments in these difficult problems are based on the use of both observed data and the results of numerical modeling, and have led to quite different conclusions. The climatic warming of the last decades was characterized by the spatial structure similar to that of the ENSO event. But since there are no data on such a structure for the whole century, the observed structure of warming is assumed to be a manifestation of the multi-decadal natural variability of climate, not the result of greenhouse forcing. 

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