Reconstruction of the climatic changes from borehole temperature and tree rings in the Kamchatka Peninsula

我们用地热和树木年代学两种独立的方法估算了堪察加半岛过去几个世纪的气候变化。作为地热方法的研究，我们在2000年至2002年进行了三次考察，在北纬53度附近的10个钻孔中重复测量了温度剖面。其中6个钻孔的温度剖面可重建地表温度历史，表明近50 ~ 100年温度显著升高1 ~ 2 K。我们还在三个钻孔的特定深度进行了长期的温度监测，观测到的时间变化表明存在小规模的水对流和地下水流量的季节变化。地下水样本取自进行温度测井的钻孔，地表水样本也取自河流。分析了地下水和地表水的地球化学特征和稳定同位素特征，进一步评价了地下水流动对研究区地下温度和气候重建的影响。利用2001年在克罗诺茨基国家公园（Kronotsky National Park）自然生长的落叶松（落叶松germerinii）的年轮岩心，在2000年的勘察基础上，建立了代表堪察加中部地区422年的年轮宽度指数年表。年代学对观测气候的响应分析显示，其与初夏气温的相关性显著。基于树木年代学及其对气候的响应，重建了1624年以来的温度，显示了近130年的总体升温趋势和年代际周期的周期振荡。长期趋势与井内温度剖面的结果一致。根据钻孔温度剖面重建了韩国的3口井和琵琶湖沿岸的1口井的地表温度历史。在韩国，估计的温度变化与附近气象站的气温数据一致。琵琶湖的地表温度历史似乎反映了当地近5000年的环境变化。少

We estimated climate changes in the Kamchatka Peninsula over the last few centuries with two independent, geothermal and dendrochronological methods.As studies with the geothermal method, we conducted three expeditions in 2000 to 2002 to make repeated measurements of temperature profiles in ten boreholes around 53 degN. The ground surface temperature history could be reconstructed from the temperature profiles in six of the boreholes, demonstrating a significant temperature increase of 1 to 2 K for the last 50 to 100 years. We also made long-tem temperature monitoring at some specific depths in three boreholes and observed temporal variations which suggest the existence of small-scale water convections and seasonal changes in groundwater flow. Groundwater samples were taken from the boreholes where temperature logging was made and surface water samples were also collected from rivers. Geochemical and stable isotope characteristics of the groundwater and surface water were analyzed to e … More valuate the effects of the groundwater flow on the subsurface temperature and climate reconstruction in the study areas.A 422-year long chronology of ring-width indices representing central Kamchatka was established from tree-ring cores sampled from Larix gmerinii growing natural in the Kronotsky National Park in 2001 based on reconnaissance in 2000. Response analysis of the chronology against observed climate revealed a significant correlation with early-summer temperature. The reconstructed temperature extending back to A.D. 1624 based on the dendrochronology and its response to climate, revealed a general warming trend over the last 130 years and a cyclic oscillation of decadal period. The long-term trend is consistent with the result from the borehole temperature profiles.Reconstruction of the ground surface temperature history from borehole temperature profiles was also made for three wells in Korea and one well on the coast of Lake Biwa. In Korea, the estimated temperature changes are consistent with the air temperature data at nearby meteorological stations. The surface temperature history by Lake Biwa appears to reflect local environmental changes for the last 5000 years. Less