What are the regional vulnerabilities in the availability of fresh water to support human needs and sustain freshwater biodiversity, and how can these vulnerabilities be mitigated?

Fresh water is multi-user resource subject to multiple threats including over-exploitation and contamination such that both quantity and quality of water is absolutely limiting for humans in many parts of the globe. Freshwater ecosystems support around 10% of global biodiversity (in less than 1% of the Earth’s surface area), and provide valuable ecosystem services upon which humans depend. Growing human water demands are placing increasing pressure on the ability of freshwater ecosystems to meet human needs, and degrading the capacity of fresh waters to sustain biodiversity. There is evidence that freshwater biodiversity is already undergoing pandemic decline, but responses to these declines at regional or larger scales are lacking. Global climate change and burgeoning populations will exacerbate present conflicts between humans and nature as demands for fresh water increase, but the vulnerability of fresh water biodiversity to impacts arising from this conflict will vary regionally. It is imperative that we identify which regions are now – and which will be – most vulnerable with respect to human needs for water and potential biodiversity loss. These data will provide an essential first step to devising adaptation and mitigation measures intended to ensure that human water requirements can be met without loss of biodiversity or irreparable degradation of freshwater ecosystem function.

Where is the missing atmospheric carbon dioxide?

About 25 to 35% of the carbon dioxide released to the atmosphere is missing according to the 2007 IPCC Report.

Understanding the mechanisms that are removing this missing carbon dioxide from the atmosphere will improve predictions of future carbon dioxide levels, estimates of future global warming, and be useful for evaluation atmospheric carbon dioxide mitigation strategies.

The search for the “missing sink” has been going on for decades. Broecker et al. (1979) identified this problem. A paper written by Tans et al. (1990) launched a major research effort to find the missing sink.

After three decades of research, scientists still do not have a full understanding of the “missing sink.” This is the most important question facing Earth System researchers at present.

References

Broecker, WS, T. Takahashi, HJ Simpson & TH Peng. 1979. “Fate of Fossil Fuel Carbon Dioxide and the Global Carbon Budget.” Science, 206, 409-418.
DOI: 10.1126/science.206.4417.409

IPCC, 2007. www.ipcc.ch

Tans, PP, IY Fung, T Takahashi. 1990. “Observational Constraints on the Global Atmospheric CO2 Budget.” Science, Vol. 247, pp. 1431-1438.
DOI: 10.1126/science.247.4949.1431

Is there a critical global temperature rise at which the biosphere will switch from being a net sink of CO2 to being a net source?

Current plans to mitigate climate change assume that reducing anthropogenic emissions of CO2 will eventually stop the increase in atmospheric concentrations. There is concern, however, that rising temperatures could trigger changes in the biosphere such that the biosphere becomes a net source. If such a critical temperature exists, exceding it would have catastrophic consequences.

How can we better monitor, model, and predict the interdependent impacts of alternative strategies for managing the global environment in support of future decision making?

Significant changes are already under way in the Earth’s environment at local, regional, and global scales. Increasing attention is being given to proposals for mitigating or modifying human drivers of environmental change, as well as to alternative strategies for adaptation and environmental management. These policy alternatives could themselves have important impacts on the environment and on human activities and welfare, and may also have unexpected or synergistic interactions, e.g., mitigation strategies that increase or shift vulnerabilities to climate change. The Earth systems research community will be increasingly called upon to assess the potential benefits and risks of specific options and of alternative strategies (e.g., geoengineering vs. adaptation). A particular concern is the potential for conflicting approaches to be adopted by different nations, groups of nations, or other stakeholders. It is essential to start now to develop the data, models, tools, and strategies needed to support better and more rapid decision making with regard to management of the global environment, even in the face of continuing scientific uncertainties and incomplete information.

Given the predominant theme:”to take action against global environmental change”, and the fact that environmental change is an ongoing process with long term consequences, what is being done in terms of research to find solutions leading to adaptation as well as mitigation of the effects on the earth and humanity to these changes?

Negative environmental change is widely perceived and agreed upon by most scientific and policy formulation circles. Too much effort is going into how to stop it, rather than how to adapt to it, for it is now inevitable and beyond the immediate control of humanity, therefore adaptation must take precedence over, or at the very least run parallel to mitigation, in order to ensure long term solutions for the earth and humanity.

Can the biotic component of ecosystems make a difference in the ways that global change impacts wellbeing, and in the way we mitigate these impacts?

Biodiversity, or the biotic component of ecosystems, has the potential to influence strongly the impacts of global change, and the ways in which people mitigate them. However, much knowledge is still lacking as to in what cases this is important, and how it operates, and in which cases (regions, processes, scenarios) the biodiversity of ecosystems is irrelavant to climate change impacts and mitigation.

Are there scientifically and politically viable ways to counter-act the most serious consequences of human-induced climate change (i.e., loss of the Arctic, diversion of storm tracks, intensification of weather extremes, acidification of the environment, etc.) for at least the several decades of peak climate change that are inevitable even in the face of aggressive international action? How much more intensive would the impacts and counter-acting actions have to be if international action is delayed for several decades?

With fossil fuels providing about 80% of global energy, it is going to take decades to decarbonize the energy system even with aggressive mitigation. As a result, it is virtually inevitable that the warming will head well past 2 C, leading to significant and likely irreversible impacts to climate, the environment, sea level, and acidification. The only potential way to keep the increase in global average temperature increase below 2 C (especially as SO2 emissions and aerosols decrease) and to limit some of the most severe impacts (e.g., to save the Arctic) is going to be to take counter-acting actions (often called geoengineering), We must determine if the potential to take such actions is scientifically justifiable, environmentally effective, and societally and politically acceptable–if research proves this so, we should be preparing to start soon to offset each year’s warming influence and perhaps take the climate back several decades; if not, we need to redouble and redouble our mitigation efforts.

How will promising mitigation strategies be optimized through methodologies and approaches that truly reflect the needs and dynamics of humanity outside the scientific community?

Towards a vision of science that resides within the global community, not apart from the realities of life.

Climate change reveals the disconnected nature of various pools of human talent, resources and endeavors. In order to overcome the unprecedented challenge of climate change we must break down the walls and learn how our institutions and mindsets need to change so that all branches of human endeavor are coordinated into one effective body social.

Science is tasked with leading the way in changing itself. The benefits will expand beyond the successful resolution of the climate crisis.

It’s time to reinvent ourselves and re-examine the origins of science for clues to our future.

How can we foster social change on the scale needed to mitigate climate change, curtail the loss of biological diversity, and halt the destruction of large terrestrial and marine ecosystem, without diminishing efforts to achieve other fundamental goals, such as the MDGs?

Efforts to address problems ike climate change cannot succeed on a business-as-usual basis. Success will require profound changes in modern industrial societies of a sort that is not well understood, much less achieveable on a managed basis. We must also acknowlege the importance of pursuing other fundamental goals, like the MDGs, simultaneously. The great issue of our time is to learn how to achieve sustainable human-environment relations.

How will Carbon markets improve adaptation to climate change in Africa?

Since the launch of the Kyoto Protocol, two main directions have been taken to respond to climate change impacts. one is to develop mitigation strategies with important reduction of CO2; second is to develop adaptation strategies for vulnerable community. These two strategies are quite well separated. this question tries to investigate the natural links between mitigation and adaptation using the green economy appended to carbon markets in Africa. Recently we discussed the issue of whether carbon can buy food, because of large carbon and biofuel projects carried out in Africa whereas small efforts are dedicated to adaptation measures. The issue raised several sub themes such as equity, ethics, african priorities in climate change issues, etc. In other words, is it more important to develop mitigation projects instead of adaptation projects.