# Global Database of Borehole Temperatures and Climate Reconstructions - CA-9610 #--------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #--------------------------------------------------------------- # # NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. # If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/1001325 # Online_Resource: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/CA-9610.html # # Archive: Borehole # # Parameter_Keywords: reconstruction #------------------------- # Contribution_Date # Date: 2016-10-16 #------------------------- # Title # Study_Name: Global Database of Borehole Temperatures and Climate Reconstructions - CA-9610 #------------------------- # Investigators # Investigators: Huang, S.; Pollack, H.N.; Shen, P.Y. #------------------------- # Description_Notes_and_Keywords # Description: This project has as its goal the design, assembly, analysis and interpretation of geothermal observations on # continents relevant to understanding the nature and causes of climate change over the past five centuries. The project was # inititated by the Geothermal Laboratory of the University of Michigan, USA. Important collaborations have been developed # with the Geophysical Institute of the Czech Academy of Sciences, and with a working group of the International Heat Flow # Commission of IASPEI. Funding for this project has come from the U.S. National Science Foundation, the U.S. National # Oceanic and Atmospheric Administration, the International Geological Correlation Program, and the Czech - U.S. Science and # Technology Program. The principal components of the database are: # (1) Basic geothermal observations from field surveys and laboratory measurements, principally comprising borehole # temperature logs and thermophysical properties. This section includes data only from boreholes at least 200 m deep. The # data listed are restricted to the range 20-600 meters. Data above 20 m have been omitted because they include annual # variability, and data below 600 m have not been included because they contain no information about the past 500 # years.Quality control measures have occasionally required the deletion of other data within the 20-600 m range. # (2) A five-century ground surface temperature history derived for each site by a standardized inversion procedure # operating on the basic observations. The derived history is presented as century-long temperature trends for each of the # past five centuries. This representation emphasizes longer term variations of the climate history, and thus is # complementary to high resolution proxies such as tree rings, ice cores, corals and lake sediments. # (3) The name of the person who can be contacted to learn more about the data and the site. This is either the name of the # original investigator who made the observations, or the name of a regional or national data compiler. Some data remain # proprietary, and therefore are not accessible directly from this database. Database users desiring access to these data # should request the data directly from the person listed as the data contact. A list of investigators engaged in climate # studies involving geothermal data can be found at the original web site of this database at the University of Michigan. # # Updated version of dataset submitted by Huang in October 2016. #-------------------- # Publication # Authors: Huang, S., Pollack, H. N., and Shen, P.Y. # Published_Date_or_Year: 2000-02-17 # Published_Title: Temperature trends over the past five centuries reconstructed from borehole temperatures # Journal_Name: Nature # Volume: 403 # Edition: # Issue: # Pages: 756-758 # DOI: 10.1038/35001556 # Abstract: For an accurate assessment of the relative roles of natural variability and anthropogenic influence in the Earth's climate, reconstructions of past temperatures from the pre-industrial as well as the industrial period are essential. But instrumental records are typically available for no more than the past 150 years. Therefore reconstructions of pre-industrial climate rely principally on traditional climate proxy records, each with particular strengths and limitations in representing climatic variability. Subsurface temperatures comprise an independent archive of past surface temperature changes that is complementary to both the instrumental record and the climate proxies. Here we use present-day temperatures in 616 boreholes from all continents except Antarctica to reconstruct century-long trends in temperatures over the past 500 years at global, hemispheric and continental scales. The results confirm the unusual warming of the twentieth century revealed by the instrumental record6, but suggest that the cumulative change over the past five centuries amounts to about 1 K, exceeding recent estimates from conventional climate proxies. The strength of temperature reconstructions from boreholes lies in the detection of long-term trends, complementary to conventional climate proxies, but to obtain a complete picture of past warming, the differences between the approaches need to be investigated in detail. #---------------------- # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: 1202673 #---------------------- # Site_Information # Site_Name: CA-9610 # Location: Canada # Northernmost_Latitude: 54.66 # Southernmost_Latitude: 54.66 # Easternmost_Longitude: -102.06 # Westernmost_Longitude: -102.06 # Elevation: #------------------------- # Data_Collection # Collection_Name: CA-9610-borehole # Earliest_Year: 1500 # Most_Recent_Year: 200 # Time_Unit: AD # Core_Length: # Notes: Data Contact: J-C Mareschal (CA) # Pre-1500 Baseline GST (oC): 2.38 # Date (Century) Rate of GST Change(K/100a) # 16th -0.353 # 17th -0.191 # 18th 0.053 # 19th 0.253 # 20th 0.413 # Date of logging (Year): 1996 # Thermal Conductivity (W/m/K): 3.60 # Geothermal Gradient (K/km): 6.20 # #------------------------- # Chronology_Information # Chronology: #------------------------- # Variables # # Data variables follow (marked with '##') # Variables list: shortname-tab- 9 components: what, material, error, units, seasonality, archive, detail, method, Temperature for Character or Numeric data ## depth_m depth,,, m,,,below surface,,N ## temp_meas temperature,,,degrees Celsius,,borehole,measured,,N #------------------------- # Data: # Missing Values: NA depth_m temp_meas 24.39 2.916 32.56 2.849 40.76 2.827 48.95 2.849 57.14 2.905 65.33 2.983 73.52 3.065 81.61 3.152 89.71 3.242 97.82 3.336 105.94 3.421 114.08 3.507 122.22 3.597 130.25 3.691 138.30 3.784 146.36 3.881 154.43 3.992 162.52 4.090 170.57 4.166 178.58 4.245 186.54 4.337 194.45 4.420 202.54 4.512 210.61 4.607 218.66 4.703 226.68 4.796 234.69 4.892 242.68 5.015 250.45 5.133 258.22 5.235 265.99 5.325 273.76 5.420 281.53 5.508 289.24 5.605 296.88 5.693 304.45 5.768 311.95 5.847 319.38 5.943 326.80 6.020 334.14 6.102 341.49 6.181 348.85 6.271 356.22 6.342 363.58 6.428 370.93 6.515 378.27 6.590 385.59 6.677 392.91 6.756 400.10 6.839 407.17 6.922 414.31 7.004 421.55 7.091 428.86 7.170 436.06 7.255 443.21 7.336 450.30 7.415 457.35 7.495 464.36 7.580 471.28 7.647 478.14 7.716 485.04 7.791 491.98 7.864 498.99 7.944 506.02 8.028 513.08 8.111 520.17 8.192 527.27 8.264 534.41 8.342