# northamerica_usa_ak14 - Isthmus  Kodiak Island - Breitenmoser Tree Ring Chronology Data
#-----------------------------------------------------------------------
#		World Data Center for Paleoclimatology, Boulder
#				and
#		NOAA Paleoclimatology Program
#-----------------------------------------------------------------------
# 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:
#
# Original_Source_URL:
#
# Description/Documentation lines begin with #
# Data lines have no #
#
# Archive: Tree Rings
#--------------------
# Contribution_Date
#	Date: 2016-01-07
#--------------------
# Title
#	Study_Name: northamerica_usa_ak14 - Isthmus  Kodiak Island - Breitenmoser Tree Ring Chronology Data
#--------------------
# Investigators
#	Investigators:  Breitenmoser, P.; Bronnimann, S.; Frank, D.
#--------------------
# Description_and_Notes
#	Description: Data from Breitenmoser 2014 Journal of past Climate supplementary, see publication for ARSTAN standardization details
#--------------------
# Publication
#	Authors: Breitenmoser, P.; Bronnimann, S.; Frank, D.
#	Published_Date_or_Year: 2014-03-11
#	Published_Title: Forward modelling of tree-ring width and comparison with a global network of tree-ring chronologies
#	Journal_Name: Climate of the Past
#	Volume: 10 
#	Edition:
#	Issue:
#	Pages: 437-449
#	DOI: 10.5194/cp-10-437-2014
#	Online_Resource: www.clim-past.net/10/437/2014/
#	Full_Citation:
#	Abstract: We investigate relationships between climate and tree-ring data on a global scale using the process-based Vaganov–Shashkin Lite (VSL) forward model of tree-ring width formation. The VSL model requires as inputs only latitude, monthly mean temperature, and monthly accumulated precipitation. Hence, this simple, process-based model enables ring-width simulation at any location where monthly climate records exist. In this study, we analyse the growth response of simulated tree rings to monthly climate conditions obtained from the CRU TS3.1 data set back to 1901. Our key aims are (a) to assess the VSL model performance by examining the relations between simulated and observed growth at 2287 globally distributed sites, (b) indentify optimal growth parameters found during the model calibration, and (c) to evaluate the potential of the VSL model as an observation operator for data-assimilation-based reconstructions of climate from tree-ring width. The assessment of the growth-onset threshold temperature of approximately 4–6 C for most sites and species using a Bayesian estimation approach complements other studies on the lower temperature limits where plant growth may be sustained. Our results suggest that the VSL model skilfully simulates site level treering series in response to climate forcing for a wide range of environmental conditions and species. Spatial aggregation of the tree-ring chronologies to reduce non-climatic noise at the site level yielded notable improvements in the coherence between modelled and actual growth. The resulting distinct and coherent patterns of significant relationships between the aggregated and simulated series further demonstrate the VSL model’s ability to skilfully capture the climatic signal contained in tree-ring series. Finally, we propose that the VSL model can be used as an observation operator in data assimilation approaches to reconstruct past climate.
#--------------------
# Funding_Agency
#	Funding_Agency_Name: Swiss National Science Foundation
#	Grant:
#--------------------
# Site_Information
#	Site_Name: Isthmus  Kodiak Island
#	Location:
#	Country: United States
#	Northernmost_Latitude: 57.63
#	Southernmost_Latitude: 57.63
#	Easternmost_Longitude: -152.33
#	Westernmost_Longitude: -152.33
#	Elevation: 1 m
#--------------------
# Data_Collection
#	Collection_Name: northamerica_usa_ak14B
#	Earliest_Year: 1859
#	Most_Recent_Year: 1986
#	Time_Unit: y_ad
#	Core_Length:
#	Notes: {"sensitivity":"temperature"}{"T1":"5.01635898109"}{"T2":"17.955058003"}{"M1":"0.0224670233855"}{"M2":"0.376624013073"}
#--------------------
# Species
#	Species_Name: Sitka spruce
#	Species_Code: PCSI
#--------------------
# Chronology:
#
#
#
#--------------------
# Variables
#
# Data variables follow that are preceded by ## in columns one and two.
# 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, C or N for Character or Numeric data)
#
##age	age, , ,years AD, , , , ,N
##trsgi	tree ring standardized growth index, tree ring, ,percent relative to mean growth, , Tree Rings, , ,N
#
#--------------------
# Data:
# Data lines follow (have no #)
# Data line format - tab-delimited text, variable short name as header
# Missing Values: nan
#
age	trsgi
1859	1.122
1860	0.96
1861	0.877
1862	0.881
1863	0.893
1864	0.867
1865	0.96
1866	0.897
1867	0.782
1868	0.96
1869	0.946
1870	1.087
1871	0.969
1872	1.106
1873	1.03
1874	1.359
1875	1.015
1876	1.025
1877	1.15
1878	1.069
1879	1.162
1880	0.91
1881	1.118
1882	0.838
1883	1.059
1884	1.207
1885	1.101
1886	1.126
1887	0.932
1888	1.097
1889	0.864
1890	1.146
1891	1.131
1892	1.126
1893	1.182
1894	0.917
1895	0.961
1896	0.874
1897	0.815
1898	0.795
1899	1.046
1900	1.004
1901	1.105
1902	1.155
1903	1.147
1904	1.062
1905	1.156
1906	0.684
1907	0.868
1908	0.842
1909	0.907
1910	1.008
1911	0.97
1912	0.455
1913	0.289
1914	0.474
1915	0.756
1916	1.049
1917	1.282
1918	1.005
1919	0.658
1920	0.999
1921	1.142
1922	0.847
1923	1.029
1924	0.905
1925	0.903
1926	0.773
1927	0.782
1928	1.126
1929	1.277
1930	1.098
1931	1.143
1932	0.982
1933	1.018
1934	1.256
1935	1.277
1936	1.2
1937	0.78
1938	1.077
1939	1.208
1940	1.149
1941	1.226
1942	1.387
1943	1.583
1944	1.635
1945	1.387
1946	1.25
1947	1.36
1948	0.99
1949	1.069
1950	0.945
1951	0.984
1952	0.769
1953	0.751
1954	0.768
1955	0.895
1956	1.105
1957	1.281
1958	0.918
1959	1.069
1960	0.932
1961	1.1
1962	1.046
1963	0.913
1964	0.464
1965	0.479
1966	0.615
1967	0.675
1968	0.773
1969	0.771
1970	0.785
1971	0.804
1972	0.73
1973	0.664
1974	0.818
1975	0.599
1976	0.656
1977	0.81
1978	0.725
1979	1.094
1980	1.131
1981	1.374
1982	1.298
1983	1.282
1984	1.259
1985	1.24
1986	1.033