Resources

In April 2009, AGCI contributed an article to the second edition of MRI News, a publication of the Mountain Research Initiative (Switzerland) which journals global change science from mountain regions around the world. The article summarizes the efforts taken in 2008 to incorporate climate change considerations into the Roaring Fork Watershed planning process, and outlines a strategy for implementing recommended next steps.

Changes to weather and climate extremes are likely to become the most vivid and disruptive manifestations of climate change over the course of this century. While it is already understood that human-induced global warming increases the intensity and occurrence of extreme temperatures and precipitation, evidence suggests that hurricanes will also become more ferocious as the world warms. This report constitutes the first specific assessment of observed and projected changes in weather and climate extremes across North America--it details what is already known about extreme climate and weather, explains the understood causes of those events, offers projections of future weather and climate extremes, and suggests how scientific efforts can be better directed to increase understanding of this subject.

In August 2007, a meeting was held at the Aspen Global Change Institute that addressed the role of the Northern Eurasian Landmass in the global Earth system. The meeting brought together members of the Northern Eurasia Earth Science Partnership Initiative (NEEPSI) to discuss how current and future research efforts in the region can better support global climate projections. One conclusion of the meeting was that more attention be focused on local-to-regional-scale biochemistry modeling for the NEEPSI region. This and other recommendations were codified in a protocol and roadmap that were produced at the meeting.

The conclusions of Aspen Global Change Institute's 2006 summer science session "Earth System Models: The Next Generation" were published in the May 2007 edition of the World Climate Research Programme Summary Report. The synopsis brings to light what models, scenarios and strategies researchers now must consider next in order to best track emissions on both the short- and long-term scales in light of current and future techniques.The development of a new generation of climate models is underway with the expectation that future models will be able to incorporate carbon cycle dynamics and offer more accurately projected stabilization scenarios. This article lays out a roadmap for a new stage of climate modeling efforts, suggesting that two timeframes be addressed near-term (2005-2030) and long-term (2005-2100). The near-term would disregard the effects of the carbon cycle and use already committed to CO2 levels to gauge regional impacts. The long-term models would assess climate outcomes on the basis of potential policy options and incorporate carbon cycle feedbacks through the use of three different experiments (1) long-term benchmark stabilization, (2) carbon cycle response to increasing concentrations, and (3) emissions driven carbon cycle/climate.

Much progress has been made in recent years to improve climate modeling, but a failure to fully incorporate variables such as the carbon cycle prevent the accurate projection of stabilization scenarios. As a result, a next-generation of climate models is needed. This article lays out a roadmap for a new stage of climate modeling efforts, suggesting that two timeframes be addressed�near-term (2005-2030) and long-term (2005-2100). The near-term would disregard the effects of the carbon cycle and use already committed to CO2 levels to gauge regional impacts. The long-term models would assess climate outcomes on the basis of potential policy options and incorporate carbon cycle feedbacks through the use of three different experiments.

The development of a new generation of climate models is underway with the expectation that future models will be able to incorporate carbon cycle dynamics and offer more accurately projected stabilization scenarios. This bulletin lays out a roadmap for a new stage of climate modeling efforts, suggesting that two timeframes be addressed near-term (2005-2030) and long-term (2005-2100). The near-term would disregard the effects of the carbon cycle and use already committed to CO2 levels to gauge regional impacts. The long-term models would assess climate outcomes on the basis of potential policy options and incorporate carbon cycle feedbacks through the use of three different experiments (1) long-term benchmark stabilization, (2) carbon cycle response to increasing concentrations, and (3) emissions driven carbon cycle/climate.

As part of the Canary Initiative, AGCI contracted with the City of Aspen in May 2005 to author a study to determine the likely consequences of global warming on the City of Aspen. The results of study are detailed in this installment of AGCI's ongoing Elements of Change series. The report focuses on three major areas: 1. Changing climate trends and projections in Aspen and the surrounding area. 2. Socioeconomic impacts of climate change on the ski industry and, by extension, the entire local economy. 3. Ecological impacts of climate change on the Roaring Fork Valley.

In 2006, AGCI prepared a report for the City's Canary Initiative that focused on impacts to skiing but also included analysis of impacts to ecosystems, local economy, and the Roaring Fork River. Following the release of the 2006 report, the City of Aspen adopted a [Climate Action Plan] (http://www.aspenpitkin.com/Portals/0/docs/City/GreenInitiatives/Canary/C...) that called for local inventory and reductions in greenhouse gases. The adopted goal is to reduce emissions 30% by 2020 and 80% by 2050 (from 2004 base levels).

This report utilizes California as a regional case study to categorize and visualize scientific uncertainties and assess the state of the art emission and climate models with an emphasis on the regional scale. The report addresses the following key questions: 1) What are the range of possible SRES scenarios; how likely are they; how can subjective probabilities be assigned, and at what levels of confidence; what methods are most promising in such estimation; and how vexing is the lack of subjective probabilities for regional analyses for the California case study? 2) How well do GCMs do at producing meteorological variables at regional scales, and which of the various strategies to improve GCMs provide the greatest direct aid in improving knowledge of and confidence in the California regional modeling efforts and assessment strategies? 3) Utilizing California as a regional case study, how can the assessment and eventual reduction of uncertainties upstream, combined with improved downscaling models, better inform regional decision-making and resource management, and what are the stakes? 4) What elements of integrated analyses are essentially unknowable? Can robust strategies (Lempert and Schlesinger, 2000) be developed in spite of those aspects of analysis?

In recent years, the topic of abrupt climate change has risen to a place of prominence in both scientific and popular discourse. The subject of abrupt climate change was addressed at a meeting held at the Aspen Global Change Institute in 2005, and the proceedings of that meeting are summarized in this article. In short, the concern among scientists is that melting freshwater could drastically impact ocean circulation, leading to an abrupt change in global climate. Such an event is believed to have occurred in the last ice age when the world may have experienced up to a 10 degree shift in temperature. However, during the AGCI meeting scientists reported on the results of climate model runs that suggest that major disruption of ocean currents is not an anticipated outcome of global warming. The general consensus of scientists by the end of the meeting was that too much focus on abrupt climate change may serve as a dangerous distraction from addressing the more realistic concerns of climate change such as sea level rise.