# Global Database of Borehole Temperatures and Climate Reconstructions - CA-0008 #--------------------------------------------------------------- # 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/1000405 # Online_Resource: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/CA-0008.html # # Archive: Borehole # # Parameter_Keywords: reconstruction #------------------------- # Contribution_Date # Date: 2016-10-16 #------------------------- # Title # Study_Name: Global Database of Borehole Temperatures and Climate Reconstructions - CA-0008 #------------------------- # 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-0008 # Location: Canada # Northernmost_Latitude: 49.21 # Southernmost_Latitude: 49.21 # Easternmost_Longitude: -89.65 # Westernmost_Longitude: -89.65 # Elevation: #------------------------- # Data_Collection # Collection_Name: CA-0008-borehole # Earliest_Year: 1500 # Most_Recent_Year: 2001 # Time_Unit: AD # Core_Length: # Notes: Data Contact: J-C Mareschal (CA) # Pre-1500 Baseline GST (oC): 3.47 # Date (Century) Rate of GST Change(K/100a) # 16th -0.340 # 17th -0.096 # 18th 0.204 # 19th 0.420 # 20th 0.297 # Date of logging (Year): 2000.5 # Thermal Conductivity (W/m/K): 2.82 # Geothermal Gradient (K/km): 10.70 # #------------------------- # 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 23.59 4.110 31.46 4.099 39.33 4.117 47.21 4.150 55.09 4.195 62.97 4.244 70.85 4.306 78.74 4.371 86.63 4.432 94.52 4.501 102.40 4.572 110.29 4.639 118.18 4.711 126.07 4.785 133.96 4.860 141.85 4.937 149.75 5.020 157.64 5.103 165.54 5.180 173.43 5.260 181.32 5.339 189.22 5.417 197.11 5.499 205.01 5.583 212.90 5.665 220.80 5.754 228.69 5.852 236.59 5.952 244.48 6.042 252.38 6.134 260.27 6.218 268.17 6.307 276.07 6.395 283.97 6.475 291.87 6.569 299.76 6.653 307.65 6.740 315.55 6.824 323.44 6.913 331.33 6.992 339.23 7.084 347.12 7.178 355.01 7.262 362.90 7.346 370.78 7.433 378.67 7.518 386.56 7.597 394.45 7.687 402.34 7.770 410.23 7.842 418.11 7.934 426.00 8.012 433.89 8.098 441.77 8.189 449.64 8.281 457.51 8.369 465.37 8.452 473.22 8.536 481.06 8.619 488.90 8.703 496.73 8.788 504.56 8.873 512.37 8.955 520.18 9.036 527.99 9.120 535.81 9.203 543.61 9.291 551.41 9.372 559.22 9.458 567.03 9.537 574.84 9.623 582.63 9.699 590.42 9.779 598.20 9.861 605.97 9.943 613.73 10.025 621.49 10.104 629.25 10.188 636.99 10.270 644.73 10.359