# Global Database of Borehole Temperatures and Climate Reconstructions #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite original reference when using these data, # plus the Online Resource and date accessed. # # Online_Resource: http://hurricane.ncdc.noaa.gov/pls/paleox/f?p=519:1:::::P1_STUDY_ID:1001113 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/huang2000/huang-2013-CA-012-0.txt # # Reconstruction_temperature_graph_URL: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/CA-012-0.html # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Borehole #-------------------- # Contribution_Date # Date: 2013-07-26 #-------------------- # Title # Study_Name: Global Database of Borehole Temperatures and Climate Reconstructions #-------------------- # Investigators # Investigators: Huang, S.; Pollack, H.N.; Shen, P.Y. #-------------------- # Description_and_Notes # 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. # #-------------------- # 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-012-0 # Location: Land>America>North America # Country: Canada # Northernmost_Latitude: 49.42 # Southernmost_Latitude: 49.42 # Easternmost_Longitude: -82.38 # Westernmost_Longitude: -82.38 # Maximum Depth: 594.700 m #------------------ # Data_Collection # Collection_Name: CA-012-0-borehole # Data contact: Kelin Wang (CA) # Date of measurement (year): 1978.9 # Estimated prior steady state GST (°C): 5 # Estimated mean conductivity (W/m/K): 2.64 # Estimated mean thermal gradient (K/km): 10 # Notes: #------------------ # Reconstruction_Temperature: # Pre-1500 baseline GST (°C): 3.125 # # Date_Century Estimated_GST_Change(°C) Notes # 16th -0.348 # 17th -0.055 # 18th 0.370 # 19th 0.923 # 20th 2.478 # # #---------------- # Variables # # Data variables follow (have no #) # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, Temperature for Character or Numeric data) Depth_m Depth Below Surface , , , m, , , , ,N Temperature_Celsius Measurement Temperature , , , Celsius degree, , , , ,N notes notes , , , , , , , ,N #---------------- # Data: # Data lines follow (have no #) # Data line format - 9-blank-spaced text, variable short name as header # Missing Values: Depth_m Temperature_Celsius Notes 22.30 4.924 29.90 4.875 37.50 4.754 44.80 4.671 52.10 4.586 59.70 4.522 67.40 4.469 74.70 4.433 82.00 4.410 89.60 4.403 97.20 4.407 104.50 4.424 111.90 4.447 119.50 4.485 127.10 4.529 134.40 4.580 141.70 4.637 149.40 4.696 157.00 4.762 164.30 4.826 171.60 4.892 179.20 4.960 186.80 5.023 194.20 5.093 201.50 5.159 209.10 5.230 216.70 5.307 224.00 5.383 231.30 5.459 239.00 5.532 246.60 5.608 253.00 5.671 253.90 5.694 260.30 5.746 261.20 5.779 267.30 5.819 275.00 5.896 282.50 5.971 290.20 6.063 297.20 6.138 304.80 6.224 311.80 6.305 319.70 6.378 327.10 6.463 334.40 6.539 342.00 6.627 349.30 6.696 357.00 6.773 364.20 6.848 371.60 6.928 378.90 6.998 386.80 7.080 392.30 7.149 401.40 7.229 408.40 7.295 416.10 7.373 423.70 7.460 430.70 7.545 438.60 7.613 446.00 7.694 453.00 7.766 460.60 7.839 468.20 7.913 475.20 7.988 483.10 8.066 490.10 8.133 498.00 8.212 505.40 8.284 512.70 8.366 520.30 8.436 527.30 8.510 535.00 8.587 542.50 8.670 549.60 8.743 557.20 8.818 564.50 8.894 571.80 8.970 579.40 9.044 587.00 9.121 594.70 9.195