# Global Database of Borehole Temperatures and Climate Reconstructions - IN-Elur #--------------------------------------------------------------- # 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/1000566 # Online_Resource: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/IN-Elur.html # # Archive: Borehole # # Parameter_Keywords: reconstruction #------------------------- # Contribution_Date # Date: 2016-10-16 #------------------------- # Title # Study_Name: Global Database of Borehole Temperatures and Climate Reconstructions - IN-Elur #------------------------- # 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: IN-Elur # Location: India # Northernmost_Latitude: 11.80 # Southernmost_Latitude: 11.80 # Easternmost_Longitude: 78.00 # Westernmost_Longitude: 78.00 # Elevation: #------------------------- # Data_Collection # Collection_Name: IN-Elur-borehole # Earliest_Year: 1500 # Most_Recent_Year: 200 # Time_Unit: AD # Core_Length: # Notes: Data Contact: S. Roy (IN) # Pre-1500 Baseline GST (oC): 29.979 # Date (Century) Rate of GST Change(K/100a) # 16th 0.016 # 17th 0.048 # 18th 0.121 # 19th 0.336 # 20th 1.958 # Date of logging (Year): 1997 # Thermal Conductivity (W/m/K): 2.20 # Geothermal Gradient (K/km): 19.70 # #------------------------- # 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 21.00 32.793 24.00 32.694 27.00 32.594 30.00 32.510 33.00 32.426 36.00 32.348 39.00 32.293 42.00 32.230 45.00 32.185 48.00 32.136 51.00 32.112 54.00 32.084 57.00 32.064 60.00 32.057 63.00 32.053 66.00 32.053 69.00 32.057 72.00 32.067 75.00 32.077 78.00 32.098 81.00 32.112 84.00 32.147 87.00 32.171 90.00 32.199 93.00 32.233 96.00 32.268 99.00 32.300 102.00 32.335 105.00 32.373 108.00 32.415 111.00 32.447 114.00 32.485 117.00 32.535 120.00 32.577 123.00 32.623 126.00 32.658 129.00 32.726 132.00 32.765 135.00 32.811 138.00 32.850 141.00 32.897 144.00 32.943 147.00 33.001 150.00 33.051 153.00 33.109 156.00 33.156 159.00 33.207 162.00 33.254 165.00 33.305 168.00 33.360 171.00 33.429 174.00 33.480 177.00 33.532 180.00 33.587 183.00 33.639 186.00 33.698 189.00 33.750 192.00 33.810 195.00 33.869 198.00 33.925 201.00 33.981 204.00 34.034 207.00 34.091 210.00 34.151 213.00 34.208 216.00 34.253 219.00 34.310 222.00 34.364 225.00 34.425 228.00 34.486 231.00 34.543 234.00 34.605 237.00 34.655 240.00 34.721 243.00 34.779 246.00 34.841 249.00 34.900 252.00 34.958 255.00 35.029 258.00 35.096 261.00 35.167 264.00 35.222 267.00 35.282 270.00 35.333 273.00 35.389 276.00 35.445 279.00 35.497 282.00 35.553 285.00 35.605 288.00 35.657 291.00 35.710 294.00 35.759 297.00 35.811 300.00 35.860