# 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