OBSERVATIONS OF CLIMATE CHANGES

FIGURE 14-56 Temperature anomalies in the Northern Hemisphere compared to the 1881-1960 mean, calculated based on measured changes in tree ring densities. The 95% confidence limit is i0.3°C. The line shows bidecadal smoothed levels. Arrows on the lower axis mark some of the major volcanic eruptions (adapted from Briffa et al., 1998). 

For example, increased water vapor at high latitudes and the associated increased precipitation, combined with melting glaciers, due to global warming could provide a layer of less dense surface water in the northern Atlantic. Since the conveyor is driven by high-density salt water, this could shut down this global 

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Important perspectives are connected with the paleo-environmental studies by the Paleoenvironmental Arctic Science (PARCS) community (MacDonald et al., 2001) which have the principal aim of answering the question To what extent do recent observations of climate change in the Arctic reflect natural climate cycles Relevant major topics include ... 

The development of evapotranspiration in Switzerland over time is presented in Fig. 2 of Impact of Climate Change on Water Resources [88]. A marked increase in evapotranspiration can be observed since the beginning of the twentieth century. 

The thermohaline circulation dominated by the Arctic Ocean and Nordic Seas is responsible for a considerable part of the Earth s poleward heat transport and may also serve as a sink for CO2. Alterations of this circulation, as have been observed during climatic changes of the past, can affect global climate and in particular the climate of Europe and North America. ... 

This comparison showed that calculated anomalies in heat content do not differ from observational values (between 1950 and 1990) by more than 5%, with the exception (for global averaging) of data for the 1970s, when the model does not reproduce the heat content anomaly observed in this decade. On the whole, the probability that these anomalies in heat content are explained only by internal variability of the climate system does not exceed 5%, which implies the anthropogenic nature of climate change. 

Atmospheric particles influence the Earth climate indirectly by affecting cloud properties and precipitation [1,2], The indirect effect of aerosols on climate is currently a major source of uncertainties in the assessment of climate changes. New particle formation is an important source of atmospheric aerosols [3]. While the contribution of secondary particles to total mass of the particulate matter is insignificant, they usually dominate the particle number concentration of atmospheric aerosols and cloud condensation nuclei (CCN) [4]. Another important detail is that high concentrations of ultrafine particles associated with traffic observed on and near roadways [5-7] lead, according to a number of recent medical studies [8-11] to adverse health effects. 

Most commercial remote sensing endeavors focus on the observation of gradual change (hours, days or months) to enhance meteorological predictions, understand climate change, and improve crop management. To effectively characterize the battle space, the military is often interested in dynamic events occurring on much shorter timescales, from... 

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