Publication Date:
2016-11-15
Description:
Ten years ago, Paul Crutzen asked whether the time had come to consider undertaking research into intentionally intervening in the climate system so that it might be considered a policy option comparable to reducing emissions for limiting human-induced climate change. Crutzen's article pointed out how little progress had been made in reducing emissions and suggested that resurrecting decades-old ideas for imitating volcanic eruptions as a possible intervention might be needed. Today, model-based simulations, optimistically assuming that nations fulfill their commitments for future emissions reductions, project global average temperature to increase to 3-4 °C above its preindustrial level by 2100, a level that Crutzen envisioned as likely to meriting active intervention. While research has begun to explore the means for intervening globally, such interventions raise challenging issues of governance, unintended consequences, intergenerational equity, and more. Initially focusing research on potential tropospheric and surface-based approaches to altering energy flows as a means for moderating adverse regional impacts might well pose less difficult governance challenges and more regionally constrained evaluations of intended outcomes and unintended consequences. Because natural processes would tend to dissipate most types of tropospheric interventions, adjustments and even termination would be possible over periods of weeks to months. In addition to serving their particular purpose, regional interventions would also provide an opportunity for learning more about Earth system behavior and the potential effectiveness and risks of global-scale interventions, if such interventions might eventually be needed to counter-balance especially severe global consequences. Plain Language Summary Ten years ago, Paul Crutzen posed the question of whether the time had come to consider intentionally intervening in the climate system as a policy option comparable to reducing emissions for limiting human-induced climate change. Given the still limited international success along the path to the phase-out of greenhouse-gas-emitting energy generating technologies and the consequent inevitability of worsening impacts, this paper suggests that researching and potentially deploying impact-focused, regional interventions may provide a means for both moderating some of the worst impacts and improving understanding of that could be useful in preparing for global interventions, if that should eventually be viewed as necessary. Investigating and exploring early implementation of regionally and tropospheric-focused approaches that would moderate Arctic warming, tropical cyclone intensification, the increasing loss of ice from the Greenland and Antarctic ice sheets, and help in counteracting the coming loss of the sulfate offset would seem to be the highest priorities to explore.
Electronic ISSN:
2328-4277
Topics:
Geosciences
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