# 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:1001290 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/huang2000/huang-2013-CA-9305.txt # # Reconstruction_temperature_graph_URL: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/CA-9305.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-9305 # Location: Land>America>North America # Country: Canada # Northernmost_Latitude: 54.72 # Southernmost_Latitude: 54.72 # Easternmost_Longitude: -101.83 # Westernmost_Longitude: -101.83 # Maximum Depth: 600.000 m #------------------ # Data_Collection # Collection_Name: CA-9305-borehole # Data contact: Jean-Claude Mareschal (CA) # Date of measurement (year): 1993 # Estimated prior steady state GST (°C): 2.868 # Estimated mean conductivity (W/m/K): 3.6 # Estimated mean thermal gradient (K/km): 12.74 # Notes: #------------------ # Reconstruction_Temperature: # Pre-1500 baseline GST (°C): 4.110 # # Date_Century Estimated_GST_Change(°C) Notes # 16th -3.731 # 17th -0.623 # 18th 1.524 # 19th 1.684 # 20th -0.226 # # #---------------- # 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 30.00 3.177 35.00 3.188 40.00 3.214 45.00 3.251 50.00 3.289 55.00 3.341 60.00 3.388 65.00 3.446 70.00 3.503 75.00 3.558 80.00 3.626 85.00 3.691 90.00 3.748 95.00 3.826 100.00 3.888 105.00 3.955 110.00 4.034 115.00 4.098 120.00 4.185 125.00 4.250 130.00 4.323 135.00 4.409 140.00 4.474 145.00 4.556 150.00 4.622 155.00 4.697 160.00 4.771 165.00 4.857 170.00 4.936 175.00 5.025 180.00 5.096 185.00 5.169 190.00 5.241 195.00 5.332 200.00 5.416 210.00 5.557 220.00 5.703 230.00 5.875 240.00 6.019 250.00 6.173 260.00 6.321 270.00 6.474 280.00 6.623 290.00 6.735 300.00 6.887 310.00 7.022 320.00 7.153 330.00 7.304 340.00 7.414 350.00 7.542 360.00 7.673 370.00 7.789 380.00 7.920 390.00 8.047 400.00 8.177 410.00 8.274 420.00 8.417 430.00 8.527 440.00 8.644 450.00 8.769 460.00 8.876 470.00 9.005 480.00 9.118 490.00 9.233 500.00 9.341 510.00 9.454 520.00 9.567 530.00 9.680 540.00 9.813 550.00 9.928 560.00 10.041 570.00 10.174 580.00 10.265 590.00 10.393 600.00 10.512