Climate change,mitigation and adaptation with uncertainty and learning

One of the major issues in climate change policy is how to deal with the considerable uncertainty that surrounds many of the elements. Some of these uncertainties will be resolved through the process of further research. This process of learning raises a crucial timing question: should society delay taking action in anticipation of obtaining better information, or should it accelerate action, because we might learn that climate change is much more serious than expected. Much of the analysis to date has focussed on the case where the actions available to society are just the mitigation of emissions, and where there is little or no role for learning. We extend the analysis to allow for both mitigation and adaptation. We show that including adaptation weakens the effect of the irreversibility constraint and so, for this model, makes it more likely that the prospect of future learning should lead to less action now to deal with climate change. We review the empirical literature on climate change policy with uncertainty, learning, and irreversibility, and show that to date the effects on current policy are rather small, though this may reflect the particular choice of models employed.     

Survival of Vibrio parahaemolyticus under environmental stresses as influenced by growth phase and pre-adaptation treatment

In this study, the susceptibility of Vibrio parahaemolyticus in different growth phases after exposure to lethal stresses including 47 °C and 8% ethanol was first investigated. The effect of a culture's growth phase on both the heat and ethanol shock response of V. parahaemolyticus was then examined. It was found that cells of V. parahaemolyticus in the mid-exponential phase, regardless of adaptation, were most susceptible to environmental stresses, while cells in the stationary phase were least susceptible to the lethal stresses examined. Adaptation with heat shock at 42 °C for 45 min or ethanol shock with 5% ethanol for 60 min induced an increased resistance of V. parahaemolyticus to subsequent lethal stresses at 47 °C and 8% ethanol. While the adaptation treatments resulted in a reduced resistance of the test organism to pH 4.4 and 20% NaCl. Generally, the extent of changes in the resistance of V. parahaemolyticus to lethal stresses between the adapted and control cells was found to be growth phase dependent. Compared with the respective control cells, the adapted late-exponential phase cells exhibited the greatest extent of change, while the adapted stationary phase cells showed the least change in their resistance to the lethal stresses examined.