Project ARRCC: Analysis of Recent and Rapid Climatic Change

ARRCC项目：对快速和近期气候变化的分析几年到几个世纪的时间尺度上的气候变化对社会和人类有最直接的影响。然而，这些时间尺度上的变化很难预测，因为我们还没有将气候强迫因素隔离在这个频率范围内。ARRCC项目旨在评估过去气候在年度至世纪时间尺度上的变化，以便更好地了解观察到的变化的类型和程度，并评估两个可能的原因：太阳活动的变化和进入大气层的火山气溶胶的影响。ARRCC项目将制作过去500年气候变化的详细时间序列，其中包括小冰期。在此期间，太阳黑子的数量(蒙德极小值)也有了显着的减少，这使得许多研究人员提出了一些因果关系。ARRCC项目中的PI将合成这一时间间隔的定量古气候数据，并将结果与模型模拟进行比较，模型模拟因火山气溶胶浓度的变化而改变传入太阳辐射的强度和大气的反射率。这项研究之所以重要，有三个原因：1)这将是对这一重要古气候事件的首次综合；2)它将为其他研究人员提供一个严格的全球过去气候数据库；3)这将是首次对太阳辐射和火山活动对气候变化的影响进行量化的严格尝试。这项研究是美国全球变化研究计划的优先事项。

Project ARRCC: Analysis of Rapid and Recent Climate Change Climatic changes on time scales of years to centuries have the most direct impact on society and humanity. Yet changes on these time scales are hard to predict because we have yet to isolate climate forcing factors in this frequency range. Project ARRCC aims to evaluate past variations in climate on annual to century time scales in order to develop a better understanding of the types and magnitude of the changes observed as well as to evaluate two potential causes: changes in solar activity and the effects of volcanic aerosol input into the atmosphere. Project ARRCC will produce detailed time series of climate variations for the last 500 years, an interval which includes the Little Ice Age. During this interval there was also a significant reduction in the number of sunspots (the Maunder Minimum) leading many researchers to suggest some causal relationship. The PIs in Project ARRCC will synthesize the quantitative paleoclimate data for this time interval and compare the results to model simulations which vary the intensity of incoming solar radiation and the reflectivity of the atmosphere because of changes in volcanic aerosol concentration. This research is important for three reasons: 1) it will be the first synthesis of this important paleoclimate event; 2) it will produce a rigorous, global data base of past climate for use by other researchers; and 3) it will be the first rigorous attempt to quantify the effects of solar radiation and volcanic activity on climate change. This research is a high-priorty for the US Global Change Research Program.