# Global Database of Borehole Temperatures and Climate Reconstructions - US-WALL94
#---------------------------------------------------------------
#           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/1000739
# Online_Resource: http://www.earth.lsa.umich.edu/climate/RECONSTRUCTION/US-WALL94.html
#
# Archive: Borehole
#
# Parameter_Keywords: reconstruction
#-------------------------
# Contribution_Date
#   Date: 2016-10-16
#-------------------------
# Title
#   Study_Name: Global Database of Borehole Temperatures and Climate Reconstructions - US-WALL94
#-------------------------
# 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: US-WALL94
#    Location: United States Of America
#    Northernmost_Latitude: 43.74
#    Southernmost_Latitude: 43.74
#    Easternmost_Longitude: -102.23
#    Westernmost_Longitude: -102.23
#    Elevation:
#-------------------------
# Data_Collection
#    Collection_Name: US-WALL94-borehole
#    Earliest_Year: 1500
#    Most_Recent_Year: 1995
#    Time_Unit: AD
#    Core_Length:
#    Notes: Data Contact:  W.D. Gosnold (US) 
#  Pre-1500 Baseline GST (oC):  8.168
#  Date (Century)    Rate of GST Change(K/100a)
#       16th                 0.116
#       17th                 0.153
#       18th                 0.209
#       19th                 0.279
#       20th                 0.536
#  Date of logging (Year):       1994.8
#  Thermal Conductivity (W/m/K):    1.10
#  Geothermal Gradient (K/km):     36.24
#  
#-------------------------
# 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
   20.00     10.350
   21.00     10.350
   22.00     10.360
   23.00     10.360
   24.00     10.370
   25.00     10.370
   26.00     10.380
   27.00     10.390
   28.00     10.390
   29.00     10.410
   30.00     10.420
   31.00     10.430
   32.00     10.440
   33.00     10.460
   34.00     10.470
   35.00     10.500
   36.00     10.510
   37.00     10.530
   38.00     10.540
   39.00     10.560
   40.00     10.570
   41.00     10.600
   42.00     10.620
   43.00     10.630
   44.00     10.650
   45.00     10.670
   46.00     10.690
   47.00     10.720
   48.00     10.740
   49.00     10.760
   50.00     10.780
   51.00     10.810
   52.00     10.830
   53.00     10.850
   54.00     10.880
   55.00     10.900
   56.00     10.920
   57.00     10.950
   58.00     10.970
   59.00     10.990
   60.00     11.020
   61.00     11.050
   62.00     11.070
   63.00     11.100
   64.00     11.120
   65.00     11.150
   66.00     11.170
   67.00     11.200
   68.00     11.230
   69.00     11.250
   70.00     11.280
   71.00     11.300
   72.00     11.330
   73.00     11.360
   74.00     11.390
   75.00     11.410
   76.00     11.440
   77.00     11.470
   78.00     11.500
   79.00     11.530
   80.00     11.550
   81.00     11.580
   82.00     11.610
   83.00     11.640
   84.00     11.670
   85.00     11.700
   86.00     11.730
   87.00     11.760
   88.00     11.790
   89.00     11.820
   90.00     11.850
   91.00     11.880
   92.00     11.920
   93.00     11.950
   94.00     11.990
   95.00     12.020
   96.00     12.050
   97.00     12.080
   98.00     12.110
   99.00     12.140
  100.00     12.170
  101.00     12.200
  102.00     12.220
  103.00     12.250
  104.00     12.270
  105.00     12.300
  106.00     12.340
  107.00     12.370
  108.00     12.400
  109.00     12.430
  110.00     12.460
  111.00     12.500
  112.00     12.530
  113.00     12.570
  114.00     12.600
  115.00     12.630
  116.00     12.660
  117.00     12.690
  118.00     12.720
  119.00     12.750
  120.00     12.780
  121.00     12.810
  122.00     12.840
  123.00     12.880
  124.00     12.910
  125.00     12.940
  126.00     12.970
  127.00     13.000
  128.00     13.030
  129.00     13.070
  130.00     13.100
  131.00     13.130
  132.00     13.160
  133.00     13.200
  134.00     13.230
  135.00     13.270
  136.00     13.310
  137.00     13.340
  138.00     13.370
  139.00     13.410
  140.00     13.440
  141.00     13.470
  142.00     13.500
  143.00     13.530
  144.00     13.560
  145.00     13.590
  146.00     13.630
  147.00     13.670
  148.00     13.700
  149.00     13.740
  150.00     13.770
  151.00     13.810
  152.00     13.850
  153.00     13.880
  154.00     13.920
  155.00     13.950
  156.00     13.980
  157.00     14.020
  158.00     14.050
  159.00     14.090
  160.00     14.120
  161.00     14.160
  162.00     14.190
  163.00     14.220
  164.00     14.260
  165.00     14.290
  166.00     14.330
  167.00     14.360
  168.00     14.400
  169.00     14.430
  170.00     14.460
  171.00     14.500
  172.00     14.530
  173.00     14.570
  174.00     14.600
  175.00     14.640
  176.00     14.670
  177.00     14.710
  178.00     14.750
  179.00     14.780
  180.00     14.820
  181.00     14.860
  182.00     14.890
  183.00     14.930
  184.00     14.960
  185.00     14.990
  186.00     15.020
  187.00     15.050
  188.00     15.080
  189.00     15.110
  190.00     15.140
  191.00     15.190
  192.00     15.210
  193.00     15.250
  194.00     15.280
  195.00     15.320
  196.00     15.360
  197.00     15.390
  198.00     15.430
  199.00     15.470
  200.00     15.510
  201.00     15.540
  202.00     15.570