Environmental Issues

The evaluation carried out by the three working groups of the Intergovernmental Panel on Climate Change, the IPCC is the base for the 2007 climatic change synthesis report providing an extensive outlook of the change in climate as the concluding component of the IPCCs fourth assessment report.  Global warming was one of the observed changes in climate.  According to IPCC, the highest level of global warming since 1980 was observed between the 12 years period of 1995-2006. IPCC states that global warming was observed to be greater on the northern latitudes than the southern latitudes. Regions covered by land were observed to warm faster than regions covered by sea.

The three groups of the IPCC reported that global warming has remarkably led to the increase in the sea level. The rise in sea level was attributed to thermal expansion, melting of ice caps and glaciers and also the polar ice sheets. The level of snow has greatly decreased as a result of global warming with a satellite data recorded since 1978 showing a remarkable annual shrinking range of between 2.1 to 3.3. Summers are the ones that have been hit hard by the decrease in snow levels showing an annual decrease range between 5.0 to 9.8. The IPCC reported that for the last 50 years or so, coldness which was a remarkable characteristic of days and nights have been replaced by hot nights and days. Precipitation events have also increased over the same period. Increase in temperature has greatly affected the global natural resources. For example, glacial lakes have increased considerably due to changes in snow, ice and frozen grounds. The increased overflow and discharge of spring peaks in advance in many glacier and snow fed rivers have greatly affected the water bodies.

Rising water temperatures have also been attributed to the changes in the terrestrial ecosystem. Many of the observational changes in the physical and the biological system were in one way or the other related to global warming. Other effects that have been noted as a result of global warming on the natural and human environment are early planting in spring and alteration in factors that destroy the forest systems like fire and vermin. Global warming has led to increase in mortality rates related to heat in certain European regions. High temperatures have been associated with the changes in some vectors for infectious diseases and also increased levels of allergic pollen in the northern hemisphere.

Increased concentration of greenhouse gases and aerosols in the atmosphere affects the solar radiation thereby altering the energy balance of the climate system leading to the development of global warming. Greenhouse gases emission was marked to have attained a 70 increase between the periods of 1970 and 2004. Between the same periods, carbon dioxide, the main gas associated with greenhouse gases and produced mainly from combustion of fossil fuel reached an emission level of 80. Human activities were attributed to the increased levels of carbon dioxide whose concentration was recorded as 379 ppm, methane whose concentration was recorded as 1774 ppm and nitrous oxide since the year 1950. The third assessment report had indicated human influence on the environment as a major cause of disturbance that is recorded including the rise in sea levels, changes in wind patterns, increased environmental temperatures, and increased frequency of heavy precipitation events.

The natural variability cannot be held responsible for all the physical and biological variations. Several studies have been shown to have linked these variations to global warming. These studies are however hindered by the time scale, greater natural climatic variations, and non climatic factors contributors. As indicated by the IPCC, the generation of greenhouse gases is likely to increase from between 25 to 90 between the years 2000-2030 and beyond as the use of fossil fuels is not coming to an end any time soon. The IPCC projected an average increase of temperature by 0.2c per decade for the next two decades. It also projected an average rise in the sea level and surface warming. The IPCC also noted some of the regional changes that include greater warming of land, mostly marked in the northern hemispheres than the southern one, drastic reduction in snow levels due to increased depth of thawing, increased frequency of heat waves and heavy precipitation, likely increase in the strength of tropical storms, shifting of the precipitations, winds and temperature patterns poleward, and finally an increase in the precipitation levels in the high latitudes and a decrease of the same in the lower latitudes.

The IPCC also projected an increase in the river overflow and availability of water. Climatic changes are also predicted to cause a major decrease in water resources in many semi arid areas. There are some sectors and regions most likely to be affected by the adverse changes in climate which were noted. The terrestrial ecosystems were noted to be prone to climatic change effects. For example, the mountain regions are very sensitive to warming whereas the Mediterranean ecosystems are heavily affected by reduction in rainfall and precipitation reduction in the tropical rainforests. Reduction of water in low latitudes affects agriculture. Heat waves are experienced at increased frequencies in the low lying coastal regions.  Some of the regions noted to be heavily affected by the climatic changes are the Arctic, Africa due to its low adaptive capacity to climate changes, small islands where infrastructure is projected to climate changes, Asian and African megadeltas where a very large population is exposed to increase in aquatic levels. Increased levels of carbon dioxide have led to a significant decrease in the potential hydrogen concentration level in oceans.  The decrease in the hydrogen concentration of global Surface Ocean was projected to be between 0.14 and 0.35 units over the 21st century. The increased acidification of the oceans is predicted to have drastic effects to marine biosphere.

The IPCC stated some of the adverse effects of climate change projected towards various continents. In Africa, a very huge population will be greatly affected by water shortage, rainfall dependent yields will be greatly reduced, and all the population found along the low lying coastal regions will be affected by the increase in sea levels by the year 2020. Asia will face an increased reduction in fresh water availability. Asian coastal regions will be adversely affected by increased floods as a result of rise in sea water levels. Urbanization, industrialization and development in Asia will be greatly affected as they depend on natural resources which will be greatly affected by the change in climate. An increase in incidences of the diseases associated with flooding will also be experienced in Asia by the year 2050. Australia will experience an increased loss of biodiversity and by the year 2030 it will be facing a severe water shortage. Agricultural production is also projected to decrease in Australia. Increased frequency of floods will be experienced by the inhabitants of the Australian low lying coastal regions by the year 2050.

In Europe, rise in sea levels will be accompanied by increased flooding and storms. Glacier level and snow cover was projected to greatly decrease by as much as 60 by 2080. Increased heat waves and wildfires are also projected to increase the health risks in Europe. Latin America will experience a considerable loss in biodiversity, decrease in agricultural production and a reduction in the availability of fresh water. Heat waves are projected to greatly increase in the cities as the coastal inhabitants will be greatly affected by pollutions as a result of increased flooding in North America. Increase in sea levels will cause stormy floods in the small islands which will greatly erode the beaches thereby deteriorating the coastal order. Some of the low cost adaptation strategies, in addition to the existing ones, can be used to reduce susceptibility to environmental alterations.

These are rain water harvesting, adjustment of planting dates and crop varieties, development of strong infrastructure along the coastal regions, proper health action plans, and use of renewable sources of energy. However, these adaptations are complicated by the hindering blocks that limit the implementation and effectiveness of these measures. These limiting factors exist from one society to the other depending on that societys productive base. Adequate policies should be implemented to reduce the production of greenhouse gases. The international cooperation will help reduce the generation of green house gases.

The IPCC strengthened the five reasons for concern identified by the third assessment report by making them a framework to consider key susceptibilities. These are the risks posed to threatened systems that are special, risk of adverse events of weather, the distribution of impact and susceptibilities, cumulative effects, and risk of extensive singularitie. Though policies and adaptations alone cannot eliminate the effects of climate change, they can complement each other and the final result would be a considerable reduction in the risks associated with climate change. Advanced technologies which emit low levels of carbon dioxide in conjunction with proper policies and adaptations will greatly reduce greenhouse gases emission by as much as 80. Annual costs, as a result of climatic changes impact, are likely to increase. However, analytical results of ways aimed at alleviating global warming and their costs do not yet show the exact pathway to be followed where benefits exceed costs.