# 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:1001221 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/huang2000/huang-2013-CA-436-1.txt # # Reconstruction_temperature_graph_URL: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/CA-436-1.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-436-1 # Location: Land>America>North America # Country: Canada # Northernmost_Latitude: 48.30 # Southernmost_Latitude: 48.30 # Easternmost_Longitude: -82.43 # Westernmost_Longitude: -82.43 # Maximum Depth: 268.600 m #------------------ # Data_Collection # Collection_Name: CA-436-1-borehole # Data contact: Kelin Wang (CA) # Date of measurement (year): 1986.73 # Estimated prior steady state GST (°C): 6 # Estimated mean conductivity (W/m/K): 2.5 # Estimated mean thermal gradient (K/km): 20 # Notes: #------------------ # Reconstruction_Temperature: # Pre-1500 baseline GST (°C): 3.332 # # Date_Century Estimated_GST_Change(°C) Notes # 16th 0.290 # 17th 0.360 # 18th 0.443 # 19th 0.472 # 20th 0.710 # # #---------------- # 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 21.60 5.753 23.90 5.677 26.40 5.608 28.80 5.545 31.30 5.495 33.70 5.452 36.20 5.415 38.60 5.387 41.00 5.361 43.50 5.340 46.00 5.321 48.40 5.305 51.00 5.292 53.50 5.281 56.00 5.271 58.50 5.265 61.00 5.259 63.50 5.255 66.00 5.252 68.60 5.250 71.10 5.249 73.70 5.249 76.20 5.249 78.70 5.250 81.30 5.252 83.70 5.255 86.30 5.258 88.90 5.263 91.50 5.268 94.20 5.274 96.80 5.281 99.40 5.289 102.10 5.298 104.80 5.308 107.50 5.318 110.10 5.329 112.80 5.341 115.50 5.354 118.20 5.368 120.90 5.383 123.40 5.398 126.30 5.413 129.00 5.430 131.70 5.447 134.40 5.466 137.10 5.485 139.80 5.505 142.60 5.525 145.30 5.547 148.00 5.568 150.80 5.590 153.50 5.612 156.30 5.636 159.00 5.660 161.70 5.684 164.50 5.708 167.20 5.733 169.90 5.758 172.70 5.784 175.50 5.810 178.20 5.835 181.00 5.859 183.80 5.883 186.50 5.908 189.30 5.934 192.00 5.960 194.80 5.986 197.60 6.013 200.30 6.039 203.10 6.067 205.80 6.092 208.60 6.120 211.40 6.148 214.20 6.176 216.90 6.205 219.70 6.234 222.50 6.263 225.20 6.292 228.00 6.321 230.70 6.355 233.50 6.386 236.20 6.415 239.00 6.444 241.70 6.474 244.50 6.507 247.20 6.539 250.00 6.570 252.70 6.607 255.50 6.640 258.20 6.670 260.90 6.702 263.70 6.734 266.40 6.769 268.60 6.783