Climate Change Processes Research Articles

Climate change and agriculture: A Nepalese case

Despite having slight disagreements on the magnitude, timing and spatial distribution of climate change, scientists agree that the recent climate change has been much faster than in the past. This has been partly to the natural phenomenon but mostly because of human activities. There is also an agreement that the poorer nations will suffer more as a consequence of the climate change than the developed nations. In this connection, the Nepalese agriculture does not seem to gain but rather lose during the process of global climate change. Even so, serious preparedness and actions can be taken that can hopefully impede the process of climate change and slowly but surely adapt to the rapidly changing climate. To achieve that, agriculture’s role as a driving force for climate change can be condensed by taking measures that reduce the rate and volume of Greenhouse Gas emissions from agriculture on the one hand, and developing diverse and resilient plant and animals breeds, on the other, that are capable of yielding as much as the current levels or even better under the foreseen changed climatic conditions. 
 
 The Journal of AGRICULTURE AND ENVIRONMENT Vol. 8, 2007, pp. 92-95

Reply to comment by K. Caldeira et al. on “Modern-age buildup of CO2and its effects on seawater acidity and salinity”

Reply to comment by K. Caldeira et al. on “Modern-age buildup of CO₂and its effects on seawater acidity and salinity”

Assessing mitigation-adaptation scenarios for reducing catastrophic climate risk

Countries can use both mitigation and adaptation strategies to protect their citizens from catastrophic risk posed by climate change (e.g., shift in the jet stream). A nation can mitigate by reducing CO2 emissions, which reduces the probability of a catastrophic event; it can adapt by altering the infrastructure so that damages can be reduced in the event a catastrophe is realized. Herein we add to the current literature by extending the endogenous risk framework into a dynamic framework permitting analysis of both mitigation and adaptation while allowing for the dynamic process of global climate change. Our results suggest adaptation to catastrophe is a small fraction of the national climate protection budget relative to mitigation when nations cooperate fully, when damages are both continuous and catastrophic, and when nations have a short planning horizon. Adaptation becomes more important relative to mitigation when nations are unlikely to cooperate, when damages are mainly catastrophic, or when the nation’s planning horizon increases.

What environmental fate processes have the strongest influence on a completely persistent organic chemical's accumulation in the Arctic?

Fate and transport models can be used to identify and classify chemicals that have the potential to undergo long-range transport and to accumulate in remote environments. For example, the Arctic contamination potential (ACP), calculated with the help of the zonally averaged global transport model Globo-POP, is a numerical indicator of an organic chemical's potential to be transported to polar latitudes and to accumulate in the Arctic ecosystem. It is important to evaluate how robust such model predictions are and in particular to appreciate to what extent they may depend on a specific choice of environmental model input parameters. Here, we employ a recently developed graphical method based on partitioning maps to comprehensively explore the sensitivity of ACP estimates to variations in environmental parameters. Specifically, the changes in the ACP of persistent organic contaminants to changes in each environmental input parameter are plotted as a function of the two-dimensional hypothetical “chemical space” defined by two of the three equilibrium partition coefficients between air, water and octanol. Based on the patterns obtained, this chemical space is then segmented into areas of similar parameter sensitivities and superimposed with areas of high default ACP and elevated environmental bioaccumulation potential within the Arctic. Sea ice cover, latitudinal temperature gradient, and macro-diffusive atmospheric transport coefficients, and to a lesser extent precipitation rate, display the largest influence on ACP-values for persistent organic contaminants, including those that may bioaccumulate within the polar marine ecosystems. These environmental characteristics are expected to be significantly impacted by global climate change processes, highlighting the need to explore more explicitly how climate change may affect the long-range transport and accumulation behavior of persistent organic pollutants.

The scientific challenge of measuring climate change

The measurement of global climate change poses grave difficulties for scientific enquiry and policy studies. Attention has so far focused on global warming and the concentration of greenhouse gases and a detailed examination has been made of the critical elements: carbon dioxide (CO 2), methane (CH 4), nitrous oxide (N 2O) and chlorofluorocarbons (CFCs). Priority has now shifted to the refining of general circulation models (GCMs) and to the hypothesis testing that they allow. A new challenge must be met: to formulate measurements of the climate consequences of burning fossil fuels, and to identify the burdens that nations must shoulder to retard the process of global climate change. The conclusion is that policy recommendations must be reached under varying conditions of scientific uncertainty; and that a range of contingent policy strategies should be opened to discussion.