Biological CO2 mitigation via photosynthetic microbes solves best
Wang et al. ‘08
(Bei, Research Computer Scientist Scientific Computing and Imaging Institute at the University of Utah Warnock Engineering Building; “CO2 bio-mitigation using microalgae” Applied Microbiology and Biotechnology, Vol. 79, Issue 5, pp. 707-718; July 2008, Access: 6/30/14)//ck
Biological C02 mitigation has attracted much attention as an alternative strategy because it loads to production of biomass energy in the process of CO2 fixation through photosynthesis (Kondili and Kaldellis 2007; Ragauskas et al. 2006; de Morais and Costa 2007a 2007a). Biological CO2 mitigation can be carried out by plants and photosynthetic microorganisms. However, the potential for increased CO2 capture in agriculture by plants has been estimated to contribute only 3-6% of fossil fuel emissions (Skjanes et al. 2007), largely due to the slow growth rates of conventional terrestrial plants. On the other hand, microalgae, a group of fast-growing unicellular or simple multicellular microorganisms, have the ability to fix CO2 while capturing solar energy with an efficiency 10 to 50 times greater than that of terrestrial plants (Li et al. 2008: Usui and lkenouchi 1997). For this review, we define microalgae as all unicellular and simple multicellular photosynthetic microorganisms, including both prokaryotic microalgae i.e., Cyanobacteria (Cyanophyceae) and eukaryotic microalgae. e.g., green algae (Chlorophyta) and diatoms (Bacillariophyta). The microalgae-for-CO2-mitigation strategy offers numerous advantages. Firstly, microalgae have much higher growth rates and CO2 fixation abilities compared to conventional forestry, agricultural, and aquatic plants (Borowitzka 1999; Chisti 2007; Li et al. 2008). Secondly, it could completely recycle CO2 (Fig. l) because carbon dioxide is convened into the chemical energy via photosynthesis which can be converted to fuels using existing technologies (Demirbas 2004). In comparison, the chemical-reaction based CO2 mitigation approaches, as discussed above, have disposal problems because both the captured CO2 and the wasted absorbents need to be disposed of (Bonenfant et al. 2003; Yeh et al. 2001). Thirdly, as discussed previously, chemical reaction-based CO2 mitigation approaches are energy-consuming and costly processes (Lin et al. 2003; Resnik et al. 2004), and the only economical incentive for CO2 mitigation using the chemical reaction-based approach is the CO2 credits to be generated under the Kyoto Protocol. On the other hand, CO2 bio-mitigation using microalgae could be made profitable from the production of biofuels and other novel bioproducts (see later discussion). Finally, the microalgal CO2 bio-mitigation could be made more economically cost-effective and environmentally sustainable, especially when it is combined with other processes such as wastewater treatment. The utilization of wastewater for microalga cultivation will bring about remarkable advantages including the following: (1) Microalgae have been shown to be efficient in nitrogen and phosphorous removal (Mallick 2002), as well as in metal ion depletion, and combination of microalga cultivation with wastewater treatment will significantly enhance the environmental benefit of this strategy; and (2) it will lead to savings in term of minimizing the use of chemicals such as sodium nitrate and potassium phosphorous as exogenous nutrients, and (3) it will result in savings of the precious freshwater sources. Figure 1 depicts a conceptual flow-chart for the complete “recycling” of CO2 for solar energy capturing. This review strives to provide a systematic account of recent developments in the field of microalgal CO2 bio-mitigation, with a focus on microalgal strains for the fixation of CO2 from different sources, the combined CO2 mitigation and biofuel production strategy, the combines wastewater treatment and CO2 mitigation strategy, microalgal nutrition and cultivation, and microalgal biomass harvesting.
1AR- Leadership Key
If the US doesn’t take the lead no one else will—guarantees extinction
Pascual and Zambetakis 2010 (Carlos [US Ambassador to Mexico, Served as VP of foreign policy @ Brookings] and Evie [Brookings]; The Geopolitics of Energy: From Security to Survival; Energy Security; 26-27; kdf)
Among these groups, the United States has the capacity to play a pivotal¶ role. China and India will not move toward more proactive domestic¶ policies if the United States does not set the example. Along with Europe¶ and Japan, the United States has the capacity to demonstrate that green¶ technology and conservation can be compatible with growth and a foreign¶ policy that is more independent of energy suppliers. The United States also stands to benefit from accelerated commercialization of green technologies¶ and the development of global markets in energy-efficient and¶ clean energy technologies. The ability of the United States to lead, however,¶ will depend on domestic action-on whether it will undertake on a¶ national basis a systematic strategy to price carbon and curb emissions. If¶ it does the scale and importance of the U.S. market can be a driver for¶ global change. If it fails to act, then the United States will find that over¶ time the opportunity for leadership to curb climate change will be replaced¶ by the need for crisis management as localized wars, migration, poverty,¶ and humanitarian catastrophes increasingly absorb international attention¶ and resources. Eventually, its failure to act will come back to U.S.¶ borders in a way that will make the Katrina disaster seem relatively tame.
1AR- Impact Extension
Climate Change is a threat magnifier—policy making must focus on finding the best avenue to avert disaster
Pascual and Elkind 2010 (Carlos [US Ambassador to Mexico, Served as VP of foreign policy @ Brookings]; Jonathan [principal dep ass sec for policy and int energy @ DOE]; Energy Security; p 5; kdf)
Climate change is arguably the greatest challenge facing the human race.¶ It poses profound risks to the natural systems that sustain life on Earth and¶ consequently creates great challenges for human lives, national economies,¶ nations' security, and international governance. New scientific reports¶ emerging from one year to the next detail ever more alarming potential¶ impacts and risks.¶ It is increasingly common for analysts and policymakers to refer to¶ climate change as a threat multiplier, a destructive force that will exacerbate¶ existing social, environmental, economic, and humanitarian stresses.¶ The warming climate is predicted to bring about prolonged droughts¶ in already dry regions, flooding along coasts and even inland rivers, an¶ overall increase in severe weather events, rising seas, and the spread of¶ disease, to cite just a few examples. Such impacts may spark conflict in¶ weak states, lead to the displacement of millions of people, create environmental¶ refugees, and intensify competition over increasingly scarce¶ resources.¶ One of the great challenges of climate change is, indeed, the scope of¶ the phenomenon. The ongoing warming of the globe results chiefly from¶ one of the most ubiquitous of human practices, the conversion of fossil fuels¶ into energy through simple combustion. Halting and reversing climate¶ change, however, will require both unproven-perhaps even unimaginedtechnology¶ and sustained political commitment. We must change living¶ habits in all corners of the globe over the course of the next several decades.¶ We must resist the impulse to leave the problem for those who follow us¶ or to relax our efforts if we achieve a few years of promising progress. The¶ profound challenge will lie in the need for successive rounds of sustained¶ policymaking, successive waves of technological innovation, and ongoing¶ evolution of the ways in which we live our lives.
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