Global Warming — Scientific Facts, Problems and Possible Scenarios

Abstract

Global warming GW has become the most interesting problem of climatology in the second part of the th century. "y the end of the s it was finally acknowledged that global climate is warmer than during any period since . Climatic modeling, including the greenhouse effect theory, started to develop intensively and the Intergovernmental Panel on Climate Change IPCC was founded by the United Nations Environment Programme and the World Meteorological Organization. This organization aims at assessing the scientific information of the risk of human-induced climate change and prediction of the impact of greenhouse effect according to existing climate models. The problem of global warming has also moved from the realm of scientific debates into global and local political spheres. What is the physical mechanism of GW? Does it result only from anthropogenic activity especially the burning of fossil fuels or do some other natural climatic phenomena contribute to the global temperature increase, too? What is the magnitude and pattern of the warming? "nswers to these questions can provide us valuable information about potential climate changes in future decades and, hence, is of crucial importance for all human activity. However, in order to answer the above questions, we need detailed information about past climatic variability and its causes. Unfortunately, substantial gaps exist in our knowledge concerning the dynamics of climate variability. The available instrumental meteorological records are sparse and irregularly distributed. They usually cover no more than the last years. Paleoclimatic proxy records reconstructions from natural archives are irreplaceable tools in filling the gaps in our knowledge about long-term climatic changes. However, the paleodata are less accurate and their reliability quite often raises serious doubts. On the other hand, modern climate models include numerous parameters, some of which are not defined adequately enough. Therefore an integrated analysis using different approaches is necessary to obtain a clearer picture of the global warming. . Global warming in the context of instrumental dataThe average temperature of the Earth, measured by the surface weather station thermometers, has increased appreciably during the last century. The IPCC consortium reported that the global mean surface temperatures have risen by . °C ± . °C when estimated by a linear trend over the last years [ ] Figure " ."ccording to a currently widely held view, the temperature rise is a mainly a result of anthropogenic emissions of greenhouse gases CO , CH , N O, halocarbons and b extremely high and unprecedented in a historical context see e.g. [ ] . It is, however, evident that the instrumentally recorded temperature data are not representative enough to support solid conclusions. Even during the last few decades the weather station network covers less than % of the land, i.e. no more than % of the Earth s surface see Figure " . Moreover, the scarcity of spatial coverage of these data generally increases going back in...

Will a New Little Ice Age Begin in the Next Few Decades?

“…5, No. 3;2013 Krivova, Balmaceda, & Solanki, 2007), but they all are based on rather arbitrary assumptions and have only a hypothetical character. Thus, the downward tendency in Wolf number during the last three cycles does not automatically result in a corresponding trend in TSI.…”

“…Instead large-scale long-term variability is dominated by linear trends (Figures 2A, B, C These spectra show a more detailed picture of long-term global temperature variability. Even after removing the overall long-term trends none of the proxy records has a dominant 200-year cycle (Figure 3) and some of them have no bi-centennial temporal variation at all (see also Figure 4 in Ogurtsov, Lindholm, & Jalkanen (2013)). …”

“…5, No. 3;2013 use the reconstructions of Loehle (2007) and Moberg, Sonechkin, Holmgren, Datsenko and Karlen (2005). A non-linear prediction was made by means of analogue method based on the reconstruction of trajectory of dynamical system of the forecasted series in pseudo-phase space -a modification of the method used by Sugihara and May (1990).…”

“…A non-linear prediction was made by means of analogue method based on the reconstruction of trajectory of dynamical system of the forecasted series in pseudo-phase space -a modification of the method used by Sugihara and May (1990). The result of a nonlinear prediction based on temperature reconstructions of Loehle (2007) and Moberg, Sonechkin, Holmgren, Datsenko and Karlen (2005) show (Figure 4) (see also Figure 11 in Ogurtsov, Lindholm and Jalkanen (2013)) that if we practically ignore the greenhouse forcing, the forecasted mean temperature of the Northern Hemisphere in the first half of the 21 st century most likely will be lower than the modern value. Till 2050 it can drop by 0.3-0.5 o C, i.e.…”

Galactic Cosmic Rays and Low Clouds: Possible Reasons for Correlation Reversal

“…The correlation coefficients between globally averaged values of low cloud anomalies (LCA) according to the ISCCP-D2 satellite data and the counting rate of the Huancayo neutron monitor amount to 0.63 and 0.92 for unsmoothed values and 12-month running averages, respectively, for the period 1984-1994. However, in the second part of the 1990s the positive correlation LCA-GCR started weakening and broke down completely near 2000 [22,23]. The observed violation of LCA-GCR correlation caused doubts in a possible influence of cosmic rays on cloud formation, as well as their important role in the physical mechanism of solar-atmospheric links [22,24,25].…”