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[en] The medium and extreme temperature time series of the stations at the airports mentioned in the Spanish abstract show increased trends in the mean temperature, especially at the airport in Medellin, which has the highest values due to the heat island effect that resulted from the airport's gradually being engulfed by the city. Likewise, it is noted that the periods from 1979 to 1982 and 1985 to 1994-95 have been relatively warm, whereas the years of 1974 to 1976 and 1984 to 1988 were relatively cool. It is also noted that the El Nino and La Nina events do influence the air temperature at those stations, which shows up as an increase or decrease of temperature, respectively
[en] The climatic change is one of the most sensible questions of the 21. century. Some denounce the human activities in the increasing of the temperatures, others prefer to point the uncertainties on the subject and speak of natural phenomena. This book discusses this confusion in order to present the arguments and motivations of the different points of view. It presents the climate changes and the researches on the greenhouse effect. It analyzes the causes and consequences. It presents also the alternative energies and the ways of facing the evolutions. (A.L.B.)
[en] Climate change is leading to a disproportionately large warming in the high northern latitudes, but the magnitude and sign of the future carbon balance of the Arctic are highly uncertain. Using 40 terrestrial biosphere models for the Alaskan Arctic from four recent model intercomparison projects - NACP (North American Carbon Program) site and regional syntheses, TRENDY (Trends in net land atmosphere carbon exchanges), and WETCHIMP (Wetland and Wetland CH4 Inter-comparison of Models Project) - we provide a baseline of terrestrial carbon cycle uncertainty, defined as the multi-model standard deviation (σ) for each quantity that follows. Mean annual absolute uncertainty was largest for soil carbon (14.0±9.2 kgCm-2), then gross primary production (GPP) (0.22±0.50 kgCm-2yr-1), ecosystem respiration (Re) (0.23±0.38 kgCm-2 yr-1), net primary production (NPP) (0.14±0.33 kgCm-2 yr-1), autotrophic respiration (Ra) (0.09±0.20 kgCm-2 yr-1), heterotrophic respiration (Rh) (0.14±0.20 kgCm-2 yr-1), net ecosystem exchange (NEE) (-0.01±0.19 kgCm-2 yr-1), and CH4 flux (2.52±4.02 g CH4 m-2 yr-1). There were no consistent spatial patterns in the larger Alaskan Arctic and boreal regional carbon stocks and fluxes, with some models showing NEE for Alaska as a strong carbon sink, others as a strong carbon source, while still others as carbon neutral. Finally, AmeriFlux data are used at two sites in the Alaskan Arctic to evaluate the regional patterns; observed seasonal NEE was captured within multi-model uncertainty. This assessment of carbon cycle uncertainties may be used as a baseline for the improvement of experimental and modeling activities, as well as a reference for future trajectories in carbon cycling with climate change in the Alaskan Arctic and larger boreal region. (authors)
[en] The aim of this paper was to review the temperature changes in Danubian lowland in Nitra locality in years from 1961 to 2010. Average temperatures were evaluated for decades with using mathematical statistical methods. In conclusion can be stated that it was recorded the increasing of average temperatures after decades for years 1960-2010, especially in vegetation period (April - September). The highest increase of average temperatures evaluated over decades was recorded in months May (1, 6°C), July (2, 1°C) and August (1, 6°C).
[en] This book gives descriptions of environmental pollution such as water and soil pollution, harmful chemicals substances and radiation, nature protection on wild animals, wild plants, and nature park, environmental assessment, and environmental management. It deals with the earth environment on change and the cause of the earth environment, ozone layer, global warming and acid fallout, plan for the earth control and environment information and information system.
[en] Are there grounds for concern as to the impact of global change on the future of European forests? This question is approached from the genetic angle, considering the modifications produced by climate change on the diversity and adaptive potential of forest species. In the absence of experimental data, the answers are derived from a set of arguments based on knowledge of evolutionary mechanisms involved in genetic diversity, the post-glacial history of European forests and lessons drawn from recent introductions of foreign wood species. These arguments entail less pessimistic conclusions than those generally reached for consequences attributed to global change. Even if major changes in composition could occur, past events show that genetic erosion capable of challenging the adaptive potential of species is unlikely. (author)
[en] In the framework of the Climate Plan elaborated by the french government, the neutral carbon principle must be applied to conference organization and the international travels. This guide has two main functions: heighten to allow everybody to understand the climate change impacts and problems, and bring some recommendations and tools to implement a neutral carbon conference (transport, welcome, accommodation and meal). (A.L.B.)
[en] The earth's annual mean global temperature increased by around 0,6 C during the 20 century, with wide regional differences. Even if solar activity has played some part in the mean temperature rise and some greenhouse gases are present naturally in the atmosphere, enhancing of the greenhouse effect due to the human activities is responsible for a large and increasing part of the observed warming. The work of the Intergovernmental Panel on Climate Change confirms the future increase under all scenarios. Depending on the efforts made by mankind to limit greenhouse gases emissions, the global mean temperature in 2100 could be between 1,4 and 5,8 C higher than in 2000. (A.L.B.)