# 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:1001331 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/huang2000/huang-2013-CA-9702.txt # # Reconstruction_temperature_graph_URL: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/CA-9702.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-9702 # Location: Land>America>North America # Country: Canada # Northernmost_Latitude: 55.17 # Southernmost_Latitude: 55.17 # Easternmost_Longitude: -97.46 # Westernmost_Longitude: -97.46 # Maximum Depth: 604.580 m #------------------ # Data_Collection # Collection_Name: CA-9702-borehole # Data contact: Jean-Claude Mareschal (CA) # Date of measurement (year): 1997 # Estimated prior steady state GST (°C): 0.861955 # Estimated mean conductivity (W/m/K): 2.8 # Estimated mean thermal gradient (K/km): 16.254 # Notes: #------------------ # Reconstruction_Temperature: # Pre-1500 baseline GST (°C): 1.080 # # Date_Century Estimated_GST_Change(°C) Notes # 16th -0.699 # 17th -0.206 # 18th 0.330 # 19th 0.653 # 20th 0.083 # # #---------------- # 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 29.54 1.409 39.24 1.617 48.95 1.793 58.65 1.924 68.35 2.063 78.01 2.199 87.67 2.342 97.33 2.498 106.99 2.638 116.65 2.777 126.31 2.923 135.97 3.067 145.63 3.230 155.29 3.377 164.95 3.529 174.60 3.690 184.26 3.836 193.92 4.014 203.58 4.165 213.24 4.332 222.90 4.488 232.56 4.655 242.22 4.820 251.83 4.979 261.44 5.146 271.06 5.310 280.72 5.519 290.38 5.625 300.04 5.793 319.35 6.101 329.01 6.267 338.63 6.416 348.24 6.585 357.85 6.739 367.42 6.899 376.98 7.049 386.54 7.207 396.10 7.367 405.67 7.515 415.23 7.687 424.79 7.841 434.36 7.987 443.92 8.146 453.43 8.300 462.94 8.451 472.45 8.611 481.91 8.758 491.36 8.905 500.82 9.068 510.33 9.222 519.84 9.358 529.35 9.508 538.80 9.658 548.26 9.798 557.71 9.933 567.11 10.078 576.51 10.227 585.90 10.387 595.24 10.537 604.58 10.681