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Climate Change and Species Loss, Robert Mburia, Jan. 2, 2012
Climate Change Threatens Serengeti, Robert Mburia, Jan. 4, 2012
Climate Change and Species Loss
Robert Mburia, Kenya
Original Post: Jan. 2, 2012
In 2001 the IPCC observed that, at global levels, human beings will continue to cause biodiversity losses through, inter alia, land use and land cover change, soil and water pollution and degradation, desertification, air pollution, diversion of water to intensively managed ecosystems and urban systems, habitat fragmentation, selective exploitation of species, introduction of alien species, and stratospheric ozone depletion. Such activities have dire consequences for the survival of most ecosystems, species, communities, biomes, social and economic livelihoods, as well as political systems.
"There is a direct link between climate change and biodiversity loss and species diversity loss. Organisms are habitat specific, whenever there are changes in climate; particular species will disappear from their current habitats and new species will appear." (ICLEI 2008). Ecosystems throughout history have always tended to adapt to changing climatic conditions. Activities of human beings have accelerated the rate of climate change, which is at its highest in centuries. This change has led to loss of important biodiversity and destruction of habitats. It is worth noting that biodiversity can help mitigate climate change. For example, forests help in absorbing carbon dioxide which accounts significantly to global warming.
The ICLEI (2008) observes that "The current climate changes have already led to species composition changes." As the climate gets warmer and some parts get cooler, many local species have already migrated from their habitats to areas that are better suited. As the planet gets warmer, there are more species migrating pole wards, displacing the exotic species therein.
A good example of ecosystem changes triggered by climate change is seen in the sharp decline in the African lion population by 30% between the year 1994 and 2001, due to indiscriminate killing and prey depletion, as well as climate variability (such as prolonged droughts and unusually heavy rain falls) that have triggered the outbreak of diseases and pests such as ticks leading to ecosystem imbalance. The tick infestation combined with the canine distemper virus resulted in a multiplying effect that caused untold deaths (WWF, 2011). If the projections of IPPC and other scientific bodies are anything to go by, natural ecosystems and species diversities will not only undergo changes, but potential extinction, as species seek to adapt to changes in their habitats.
Global warming has an effect on the reproductive cycles of many animals, and the shifts have direct impacts on relations among the animals. Such changes will affect all animals, both wild and domestic. Plants too will be affected and it may become difficult to obtain medicinal herbs in areas where they are in abundance. Food security too will be an issue in the years to come.
Waste management will most likely be affected by the changing climate. This will have very severe consequences on urban areas as the micro-organisms which are vital in breaking down the wastes are sensitive to temperature changes. Too much heat destroys them while very low temperatures cause them to enter a dormant mode.
Gaps in the IPCC Model Reports
The IPPC (2007) observed that "climate change will result in the extinction of many species and cause reductions in the biodiversity of ecosystems." Conversely, it should be noted that multiple drivers affect ecosystem processes, both directly and indirectly. The correlative, mechanistic and analogue (climate envelope modeling and dynamic global vegetation modeling approaches), are used to understand these effects. Nevertheless, these modeling methods underestimate the impact of climate change on extinction of species, as they fail to take into account the multiple factors that have multiplying effects on ecosystem and species changes. The climate and ecosystem models nonetheless give alarming projections of the future of species and ecosystems, maybe even more adverse than current projections.
The models also fail to include aquatic ecosystems. These are already affected by the impacts of climate change and other related negative players like filtration, eutrophication, and chemicalization that alter the PH balance of their habitat, thus bringing about habitat change. Native aquatic plants and animal species will differ widely in response to changes in water temperature and hydrology. The changes are not easy to project or determine, as some of the species may adapt to warmer temperatures, while others may move pole wards to cooler waters. But, what is most obvious is that extinction of some aquatic life and ecosystems is imminent (Union of Concerned Scientists 2009).
"Climate change is projected to affect all aspects of biodiversity" (IPCC 2002). CO2 emissions are projected to lead to a 4.4˚C increase in temperature by the end of the 21st century. Precipitation is projected to increase in high latitude areas and equatorial areas while the subtropics will see reduced precipitation with an increase in precipitation events. Land areas will experience higher temperatures than the oceans while high latitude areas will be hotter than the tropics. Sea levels will rise, causing coastal flooding, and the loss of habitats and of species in some coastal ecosystems and within the marine ecosystems. Such changes will affect individual organisms, populations, species distribution, and ecosystem composition and function (IPCC 2002), both directly, and indirectly.
Further heart breaking projections reveal that, “by the year 2080 nearly 20% of all coastal wetlands will be extinct due to rise in sea levels." Countries will lose income generated from coastal tourism activities. Such impacts cannot be ignored or just anticipated; a series of connected outcomes will result from these changes. Countries that heavily rely on coastal beaches or mangrove forests will lose their national income.
The current projections spell danger for species which are habitat specific and have restricted or specific habitat requirements. The adaptation ability of such species is low and their extinction is imminent. Such species will include mangroves, coastal wetlands, and birds in the peninsular islands, among others. Mountain species will lose their habitats should the snow melt, and as previously cold regions get warmer.
Coral reefs are home to tens of thousands of species and a variety of the world's most dense and diverse communities of vertebrate animals. However, very few remaining coral reefs still enjoy this unspoiled condition: “fish populations and corals have seen significant reductions in population (Bruno 2009 & Terence et al 2006).” Ocean warming due to climate change is leading to reduced coral cover through coral bleaching; there is also an indirect link between ocean warming and the death of corals through intensifying the effects of infectious diseases, especially in the Caribbean. Disease incidences, prevalence and impacts have been reported to have increased in these areas over the last 20 to 30 years (ibid). Bruno further states that temperature increases may lead to psychological stress in corals which may lead to mimunosuppression, making them more vulnerable to infections.
There has also been an increase in ocean acidity through the release of carbon into the atmosphere, of which a quarter enters the ocean and reacts to form carbonic acid that reduces water PH levels. Low PH levels have been known to inhibit coral growth, reducing their competitive advantage among others.
Challenges in Accurate estimates of the impacts
Downing (1992) outlined the factors that make it difficult to assess the risks of climate change to future livelihoods as follows: brisk changes in socioeconomic statuses that occur in line with global warming, as well as the complexity of the interlink ages between economic sectors and feedback, which further hinders accurate assessment. Sub-Saharan Africa has been rated among the most vulnerable regions to climate change in the world. The ecosystems in this region are generally sensitive and fragile. At the same time, most of the populations in this region rely heavily on natural resources for survival and development. These activities have been badly affected by climate change and global warming.
Downing (1992) uses the term vulnerability broadly, to encompass specific consequences such as food shortage or famine and does not just point to a cause, such as drought. Secondly, adverse consequences are not just put down to sensitivity; for example maize plants are sensitive to droughts; while households are vulnerable to hunger. Sub-Saharan Africa, especially Kenya, lies squarely in this danger zone, because the region is vulnerable to food shortage and hunger due to economic systems' sensitivity to climate change. Finally, vulnerability is taken relatively to differentiate between socioeconomic groups or regions.
Butler (2007) notes that extinction is a hotly debated, but poorly understood topic in science. The same goes for climate change. Huge conflicts have existed among the scientific bodies hindering precise understanding on the impacts of climate change on biodiversity.
Impacts on the Biomes
Climate change has various impacts on ecosystems, ecosystem diversity and species. Alterations in the world’s major biomes have had major consequences for animal, plant and human life. These biomes are classified as: aquatic, deserts, forests, grasslands and tundra. Pullen (2004) observes that biomes show an ancestral relationship that connects all organisms, present and past. The importance of biomes cannot be overestimated, as they carry diverse communities within them. Conservation of the world’s biomes and their preservation should be a concern not only to conservation bodies, but to everyone. Human activities have drastically altered these communities (Pullen 2004).
John Bruno (Lead Author); Mark McGinley (Topic Editor) "Coral reefs and climate change". In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth August 26, 2008; last revised Date September 20, 2010; Retrieved November 11, 2011
IPCC (2002) Climate Change and Biodiversity: IPCC Technical paper V. Climate Change 2007-impacts, adaptations and mitigations of climate change: scientific-technical analyses; Fourth Assessment Report 2007
COSEE-ocean systems: climate change and ecosystems; A research and discussion activity directed at grade levels 9 – 12; Union of Concerned Scientists Curriculum Guide, ICLEI (2008) Biodiversity and Climate change
Terence P. et al 2007. Phase Shifts, Herbivory, and the Resilience of Coral Reefs to Climate Change, Current Biology, Volume 17, Issue 4, 20 February 2007, Pages 360-365, ISSN 0960-9822,10.1016/j.cub.2006.12.049.
Climate Change Threatens Serengeti
Robert Mburia, Kenya
Original Post: Jan. 4, 2012
The Serengeti ecosystem cuts across the Masai Mara in Kenya and Serengeti in Tanzania. The wild beasts move between these two countries following clear paths and specific seasons. This movement alone has caused their migration to be recognized as the eighth world wonder. Climate change, as well as human activity, threatens this movement and the health of this complex ecosystem. The uncertainty of consequences of climate change means that such climatic alterations pose great risks, with past evidence proving fatal. Future predictions show worrying trends that should not be ignored. Critical decisions ought to be made to save the planet. It is estimated that global average temperatures will increase between 2˚-5˚c by 2050.
The World Wildlife Fund (WWF) www.wwf.org observes that Africa is one of the most vulnerable regions in the entire world to climate change. This concurs with the highlights of the Intergovernmental Panel on Climate Change (IPCC) on the impacts of climate change that have catastrophic effects on humans and the environment. Serengeti faces real threats, as do all other wildlife inhabitants and ecosystems, due to climate change. As clearly noted by Sinclair et al. (2008) human activity and natural changes are expected to drastically alter global climate and atmospheric chemical composition over the next five decades. These changes will badly hit isolated and complex ecosystems like Serengeti, even if they are areas protected from human activity.
Increased carbon emissions into the atmosphere have a high likelihood of altering vegetation, hydrology, plant quality to herbivores, species diversity, migration patterns, disease outbreaks among humans, fauna and flora, change or destruction of habitats among others (ibid). The natural and human populated ecosystems of Serengeti face real threats such as changes in productivity and biodiversity. Some animal and plant species may become extinct as a result of climate change related factors.
Carbon dioxide would mean more photosynthesis for plants, and may also lead to increased plant species and quality, but it may also lead to limiting resources needed by plants, thereby inhibiting their growth. Either of these changes has dire consequences for the health of Serengeti ecosystem. Altering rainfall patterns -experienced two times a year, the first ones beginning in late March to May and then October to November when there is inter-tropical convergence- will greatly increase wildlife migration. It is now noted that CO2 in the atmosphere has increased significantly worldwide.
Scientists and climatologists have raised alarms over the plight of the wild animals due to deforestation, carbon emissions from cars, factories and other areas. It is noted that although carbon may be produced in factories which may be located very far away, it is easily transported as it mixes with the atmospheric gases. Destruction of Serengeti ecosystem will not only mean loss for the animals but also human wildlife conflicts, socioeconomic conflicts, and also the expansion of vicious poverty cycles. Studies have shown that temperatures in Amboseli, which is near Serengeti, have increase by 3˚c.
The Mara River which cuts right across Serengeti has seen its water volume reduced by more than half over the past few years according to WWF project manager. The drought that is ravaging East Africa is having a toll on this ecosystem. Animals, as well as pastoral communities together with their livestock, face starvation.
Unless drastic measures are carried out by the relevant stakeholders of the developed and developing countries, the menace of climate change will bite all global ecosystems. Our planet is one big ecosystem that is made of subsets that are linked to each other. Alterations in one have consequences for the other. Serengeti will die if climate change is not curbed and green gas emission reduced, as well as increasing reforestation activities.
Together with substantial reductions in green gas emissions, there is need for policy and strategic frameworks to be developed which will ensure conservation takes place within and without protected areas.
Anthony Ronald Entrican Sinclair, Craig Packer, Simon A. R. Mduma, John M. Fryx. (2008). Serengeti 111: human impacts on ecosystem dynamics.(C. P. A.R.E. Sinclai, Ed.) Chicag, U.S.A: University of Chicago Press Ltd.
WWF: Impacts of climate change on Life in Africa, www.wwf.org