The Swedish Climate Scientist - Svante Arrhenius - Essay Example

The Swedish Climate Scientist - Svante Arrhenius INTRODUCTION Back in 1896, Svante Arrhenius, the Swedish climate scientist, published an article in the journal Philosophical Transactions. The scientist argued that doubling of carbon dioxide concentration in the atmosphere would lead to increase of the global surface temperature by approximately 9ºF (Arrhenius, 1896). Immediately after publication of the article Arrhenius faced strong opposition: his arguments and predictions were dismissed as faulty, and it was not until the last decades that the climate change finally drew attention of the scientific community and public. Starting from the early 1980s, a number of scientists from different countries across the globe have been reporting substantial increase in the atmosphere temperature. The most commonly mentioned cause of the increase is excessive volumes of carbon dioxide and several other gases being released into atmosphere in result of human activity. Pessimistic forecasts say that by the end of 21st century the overall increase in carbon dioxide concentration will cause the surface air temperature rise by 2°C to 5°C, while in the polar region the temperature may boost by 12°C (Jaworowski, 2004). Public and governmental concerns about the phenomenon of global warming peaked in 1997 when leaders of the industrially developed states gathered in Kyoto, Japan to sign a treaty limiting emissions of carbon dioxide. Despite increasing awareness of the negative effects that global warming may potentially cause, the debate on the causes and outcomes of this phenomenon is still on. Each year new publications appear claiming to finally stop this lingering dispute, but the controversy persists. The problem is that global warming is closely related to climate change: the time scale for such change is measured in centuries rather than in years or even decades, while the model of climate change includes hundreds of factors and variables; its dynamics is not fully understood. Consequently, no decisive arguments can be obtained in the short term. CAUSES OF GLOBAL WARMING Global warming is considered to depend upon two major factors: excessive emissions of carbon dioxide and other ‘greenhouse’ gases and fluctuations in temperature trends. During the last decades of the 20th century global warming was predominantly viewed as one of numerous side effects of human activity. 99.9% of the overall atmospheric volume belongs to only three gases: nitrogen (78.09%), oxygen (20.95%), and argon (0.93%). However, the climate depends on these three major gases much less than it depends upon the remaining groups of gases that constitute only 0.01% of the Earth’s atmosphere. These gases are carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), nitrogen oxides (NOx), chlorofluorocarbons (CFCs), and ozone (O3) and they are known as “…greenhouse gases or radiatively important trace species (RITS). They are radiatively important because they influence the radiation balance or net heat balance of the Earth” (Hardy, 2003: 3). For nearly three centuries the mankind has been raising the concentration of carbon dioxide and other ‘greenhouse’ gases in the atmosphere. Numerous factories, fossil fuel power plants and vehicles produce astonishing volumes of carbon dioxide; millions of tons of decomposing garbage coupled with highly increased population of methane-belching cattle result in release of excessive volumes of methane; nitrogen-containing fertilizers – the cornerstone of contemporary agriculture – raise concentration of nitrogen oxide. In figures, the rise seems rather impressive: while the preindustrial concentration of CO2 in the atmosphere did not exceed 280 ppm, these days the concentration of this gas is approximately 370 ppm which corresponds to more than 30 percent increase. The same tendency is observed in concentration of other greenhouse gases. Thus, concentration of methane and N2O has been raised by 151% and 17% respectively over the last 250 years. The Intergovernmental Panel on Climate Change (IPCC) reports these values to be the highest ever in the history of mankind: “The present CO2 concentration has not been exceeded in the last 420,000 years and likely not during the past 20 million years. The current rate of increase is unprecedented during at least the past 20,000 years” (IPCC 2001: 7). The United States holds the lead in this questionable competition. In 2004, the Energy Information Administration (EIA) estimated that emissions of the greenhouse gases in U.S. reached the absolute peak. Thus, emissions of heat-trapping gases increased by 139 million tons/2 percent over just one year; emissions of transport gases increased by 3.1 percent, while the overall volume of gases released in 2004 increased by 16 percent in comparison to 1990. In case such tendency persists, the EIA estimates a striking 38 percent increase in emissions of heat-trapping gases by 2030 (EIA, 2005). Highly increase concentrations of greenhouse gases cause serious imbalance in heat exchange taking place in the atmosphere: “Current greenhouse gas concentrations contribute about 2.4 watts per square meter of net radiative forcing, that is, incoming solar radiation exceeds outgoing radiation by 2.4 w/m2” (Sterman and Sweeney, 2002: 56). As a result, the average global surface temperature has risen by 0.6 ± 0.2 °C over the last century, which entailed retreat of glaciers, “…a decline in winter snow cover, a 40% decline in summer sea-ice thickness in the arctic, an increase in average precipitation and in extreme weather events, and a rise of 0.1 – 0.2 meters in sea level, among other effects (IPCC, 2001: 8). Vapors of water trap more heat than any other gas in the atmosphere, but the concentration of the vapors in the atmosphere practically does not depend upon human activities. Instead, the concentration is “…determined by the balance between evaporation from the earth's surface and rainfall… and… recent satellite measurements confirm that this balance tends to keep global average relative humidity … nearly constant” (Soden et al, 2005: 842). Since the vapor-holding capacity of air is proportional to its temperature, global warming leads to an increase in the amount of heat trapped by the vapors, which in its turn causes additional heating of the atmosphere. Some experts believe that this process represents a positive feedback mechanism that nearly doubles the direct heating caused by adding carbon dioxide to the atmosphere. (Soden et al, 2005). Continuous satellite observations taken over the last decade confirm validity of the water vapor feedback mechanism. Despite numerous arguments in support of human-induced greenhouse effect, many scientists argue that human activities might exert practically no influence on the process of global warming. Throughout traceable history of our planet, concentration of greenhouse gases the atmosphere changed many times. Each change was followed by certain changes in climate. Therefore, the climate developments we have been witnessing recently can hardly be considered unusual: they reflect natural planetary and solar trends. As Z. Jaworowski, the renown researcher of global warming notes “…from time immemorial, alternate warm and cold cycles have followed each other, with a periodicity ranging from tens of millions to several years…. the cycles were most probably dependent on the extraterrestrial changes occurring in the Sun and in the Sun’s neighborhood” (Jaworowski, 2004: 53). Historical analysis of known temperature variations that have occurred over the last several centuries demonstrates that since 1000 AD the range of temperature variations has been within approximately 1.5˚C. Apparently, those variations were not due to the greenhouse effect: the concentration of greenhouse gases in the atmosphere is considered to be constant until the Industrial revolution in the middle of 18th century. Surprisingly, temperature variations over the last 150 years were absolutely within this natural range: • 1860-1920 – Global temperature was about 0.3˚C cooler than the average. • 1920-1940 – Global temperature rose by about 0.35˚C to slightly above the average. • 1940-1975 – Global temperature shows a gradual cooling of perhaps 0.1˚C. • 1975-1990 – Global temperature rose above the average by about 0.3˚C (Houghton, 2001: 213). Failure of the forecast given by Arrhenius (a very similar prediction was also made by NASA scientist Hansen in the 1980’s) also provides some support to this point of view: although the concentration of greenhouse gases increased by nearly 50%, the temperature increase much less than it was predicted to (Michaels, 2002). Scientists sticking to this ‘natural variations’ point of view admit that certain terrestrial factors may have some influence on the short-term temperature changes. However, human-induced increase in concentration of greenhouse gases is not considered a highly important factor in this regard: volcanic explosions, variations in oceanic currents, thermal energy produced by natural radionuclides and some other natural phenomena contribute to the changes much less within this perspective on the global warming (Jaworowski, 2004). However, the latest research challenges credibility of the natural variations theory. Examination of air bubbles trapped in Greenland and Antarctic glaciers improved the scientists’ understanding of the ancient atmospheric trends and composition of the atmosphere. The new data confirmed that the current amount of carbon dioxide contained in the atmosphere is the highest over the last 650 thousand years. Examination of different oxygen isotopes trapped in the ice also reveal a strongly link between the temperature and concentrations of carbon dioxide (Siegenthaler et al, 2005). EFFECTS OF GLOBAL WARMING Potential effects of the global warming addressed in the relevant publications range from positive to absolutely catastrophic. For the sake of objectiveness, it is necessary to admit that pessimistic predictions prevail, especially in the last years. The major concern is the long-term consequences of global warming. However, they also admit that considering the time scale for climate change processes, the results of any corrective actions will hardly be observable in the nearest decades or even centuries. Hurricanes and heavy storms are probably the most widely discussed and feared effects of the global warming. Theoretically, the influence of global warming on intensity of hurricanes and tropical cyclones is possible due to alterations of the surface energy flux and/or the upper-level cold exhaust (Henderson-Sellers et al., 1998). However, there is absolutely no reliable data available that intensity and frequency of cyclones is linked to global warming. The data captured during one recent research demonstrates that the temperature of sea surface, which has increased as the result of global warming, is not the key factor that affects intensity and frequency of hurricanes: “The data indicate a large increasing trend in tropical cyclone intensity and longevity for the North Atlantic basin and a considerable decreasing trend for the Northeast Pacific. All other basins showed small trends, and there has been no significant change in global net tropical cyclone activity. There has been a small increase in global Category 4-5 hurricanes from the period 1986-1995 to the period 1996-2005. Most of this increase is likely due to improved observational technology” (Klotzbach, 2006). Another study conducted by a group of German scientists has demonstrated that “…the devastating floods in central Europe in 2002 were perfectly normal events when compared against the historical record” (Mudelsee et al., 2003: 168). Reliability of the predicted effects leaves much to be desired, especially when it comes to the long-term perspective. Researchers making the predictions do not have any empirical data to rely upon; instead they mostly employ computer climate modeling methods which are highly unreliable. Consequently, some scientists consider that global warming will hardly have any major impact on the everyday climate conditions, while others argue that once the planet’s surface temperature reaches certain unknown threshold, “…the heat will trigger relatively drastic changes to the atmosphere and the oceans and transform the Earth’s weather patterns in a matter of years” (NASA, 2002: 3). Another debated effect of the global warming is sea-level rise caused by melting of continental glaciers and the Greenland Ice Sheet. According the IPCC estimates, the level of sea will increase by 9 to 88cm by 2100 (IPCC, 2001). Apparently, even so slight rise of the sea level is likely to cause severe damage to highly populated coastal regions. On the other hand, the predicted rise is far from being catastrophic: the West Antarctic Ice Sheet that can potentially raise the sea-level by several meters is forecasted to remain for the nearest century at least (NASA, 2002). Biologically, global warming is predicted to alter natural habitats. Majority of these changes are considered to be negative, while some of them are believed to be positive. The negative changes comprise disappearance of certain animals, fish and plants, emergence of new deserts, while positive changes include intensive growth of forests and algae and improved life conditions for certain fish. CONCLUSIONS AND RECOMMENDATIONS While the burden of evidences proving the danger of global warming increases, governments of the world fail to pay appropriate attention to the issue, and the situation continues to get worse. Emissions of the greenhouse gases tend to go up instead of going down, and the Kyoto protocol is surrounded by controversy with some labeling it a scheme to slow down the growth of the powerful industrial states, some arguing its benefits to be overweighed and some claiming the protocol is absolutely useless. However, with all its controversy the Kyoto protocol remains the only international long-term climate agreement: the efforts of international community in this direction leave much to be desired. Individuals can also contribute to slowing down the process of global warming. Reducing of individual fossil fuel consumption, eating less beef, use of alternative energy and cutting down the traditional energy consumption are appropriate methods of doing so. Yet, none of these measures will be effective without actions undertaken by the national governments and international community. Since the Kyoto protocol failed on the large scale, other initiatives are needed to at least slow down the process of global warming. Investing money into further research of the climate change and global warming is another aspect of fighting global warming. The value of such research can hardly be exaggerated. Availability of credible scientific data will make it possible to timely and effectively respond to the potential environmental threats, envisage the need for certain actions/solutions, and finally resolve the remaining controversy over the causes and effects of global warming. Considering the cost of reducing the greenhouse gases emissions on the state and international level, such investments may be among the most successful in the history of modern world. REFERENCES Arrhenius, S., (1896) “On the influence of carbon acid in the air upon the temperature of the ground” Philosophical Transactions, 41: pp. 237–276. Energy Information Administration (EIA) (2005) Annual energy outlook 2005: with projections to 2025, DOE/EIA-0383(2005). Washington, DC: U.S. Department of Energy Hardy, John T. (2003) Climate Change: Causes, Effects, and Solutions. John Wiley & Sons, Ltd. Henderson-Sellers, A., and Coauthors (1998) “Tropical cyclones and global climate change: A post-IPCC assessment” Bulletin of American Meteorological Society, 79: pp. 9–38. Houghton, J. T. et al., Eds. (1991) Climate Change: The IPCC Scientific Assessment, Cambridge University Press, Cambridge, 1991. In addition to the IPCC, assessments have been published by the National Research Council. IPCC (2001) Climate Change 2001: The Scientific Basis. Summary for Policymakers: A Report of Working Group 1 of the Intergovernmental Panel on Climate Change. IPCC Third Assessment Report [available at www.ipcc.ch ] Jaworowski, Z. (2004), “The Ice Age Is Coming: Solar Cycles, Not CO2, Determine Climate”, 21st Century Science & Technology, Winter: pp.52-65 Klotzbach, P. J. (2006), “Trends in global tropical cyclone activity over the past twenty years (1986–2005)”, Geophysical Research Letters, vol. 33, L10805, doi:10.1029/2006GL025881 Mudelsee, M., Börngen, M., Tetzlaff, G. & Grünewald, U. (2003), “No upward trends in the occurrence of extreme floods in central Europe”, Nature 425; pp.166–169. NASA (2002) “Global Warming”, The Earth Science Enterprise Series, NF-222 [available online at http://earth.nasa.gov ] Pielke, R. A.., C. Landsea, M. Mayfield, J. Laver, and R. Pasch (2005) “Hurricanes and Global Warming”, BAMS, 8(1): pp. 1571-1575 U. Siegenthaler, T.F. Stocker, E. Monnin, D. Lüthi, J. Schwander, B. Stauffer, D. Raynaud, J.-M. Barnola, H. Fischer, V. Masson-Delmotte and J. Jouzel (2005) “Stable Carbon Cycle-Climate Relationship During the Late Pleistocene”, Science 310: pp.1313-1317 Soden, B. J., D. L. Jackson, V. Ramaswamy, M. D. Schwarzkopf,and X. L. Huang, (2005) “The radiative signature of upper tropo-spheric moistening”, Science, 310, 841–844 Sterman, John D. and Linda Booth Sweeney (2002) “Cloudy Skies: Assessing Public Understanding of Global Warming” System Dynamics Review, 18(2): pp.52-86 Read More