# northamerica_usa_ak053 - Sheenjek River - 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_ak053 - Sheenjek River - 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: Sheenjek River
#	Location:
#	Country: United States
#	Northernmost_Latitude: 68.08
#	Southernmost_Latitude: 68.08
#	Easternmost_Longitude: -143.13
#	Westernmost_Longitude: -143.13
#	Elevation: 100 m
#--------------------
# Data_Collection
#	Collection_Name: northamerica_usa_ak053B
#	Earliest_Year: 1824
#	Most_Recent_Year: 2000
#	Time_Unit: y_ad
#	Core_Length:
#	Notes: {"sensitivity":"temperature"}{"T1":"4.74979713294"}{"T2":"18.4609862925"}{"M1":"0.0217520456759"}{"M2":"0.26473569047"}
#--------------------
# Species
#	Species_Name: white spruce
#	Species_Code: PCGL
#--------------------
# 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
1824	1.064
1825	1.135
1826	0.314
1827	0.853
1828	0.975
1829	0.756
1830	0.863
1831	0.874
1832	0.639
1833	0.723
1834	0.697
1835	0.488
1836	0.784
1837	0.826
1838	0.745
1839	0.574
1840	0.422
1841	0.772
1842	0.812
1843	0.789
1844	0.721
1845	0.419
1846	0.832
1847	0.706
1848	0.856
1849	0.764
1850	0.796
1851	0.631
1852	0.597
1853	0.787
1854	0.426
1855	0.964
1856	0.986
1857	0.877
1858	0.827
1859	0.485
1860	0.687
1861	0.828
1862	0.815
1863	0.862
1864	0.682
1865	0.724
1866	0.45
1867	0.95
1868	0.486
1869	0.444
1870	0.413
1871	0.577
1872	0.761
1873	0.57
1874	0.602
1875	0.921
1876	0.585
1877	0.484
1878	0.529
1879	1.051
1880	1.13
1881	0.916
1882	1.108
1883	0.904
1884	1.226
1885	0.908
1886	0.945
1887	0.759
1888	0.544
1889	0.789
1890	0.743
1891	0.955
1892	0.492
1893	0.903
1894	0.632
1895	0.868
1896	0.994
1897	0.966
1898	0.796
1899	0.523
1900	0.788
1901	0.811
1902	0.867
1903	1.053
1904	1.07
1905	1.004
1906	1.31
1907	1.339
1908	1.308
1909	1.275
1910	1.179
1911	1.024
1912	0.665
1913	0.723
1914	0.89
1915	0.855
1916	0.678
1917	0.67
1918	0.576
1919	0.53
1920	0.637
1921	0.374
1922	0.37
1923	1.749
1924	0.907
1925	0.897
1926	1.028
1927	1.282
1928	1.046
1929	1.324
1930	1.552
1931	1.026
1932	1.196
1933	0.96
1934	1.173
1935	1.233
1936	1.082
1937	0.708
1938	0.854
1939	1.116
1940	0.777
1941	1.244
1942	1.357
1943	1.886
1944	1.971
1945	1.874
1946	1.851
1947	1.43
1948	1.093
1949	0.788
1950	1.159
1951	0.577
1952	0.886
1953	0.962
1954	1.06
1955	1.161
1956	0.966
1957	1.004
1958	0.991
1959	0.819
1960	0.977
1961	1.235
1962	1.124
1963	1.052
1964	1.181
1965	1.219
1966	1.23
1967	1.047
1968	1.137
1969	0.71
1970	0.574
1971	0.777
1972	0.901
1973	0.504
1974	0.583
1975	0.7
1976	0.577
1977	0.603
1978	0.426
1979	0.366
1980	0.65
1981	0.759
1982	1.004
1983	1.133
1984	0.967
1985	0.869
1986	1.033
1987	0.79
1988	0.622
1989	0.548
1990	0.703
1991	0.568
1992	0.508
1993	0.33
1994	0.156
1995	0.226
1996	0.722
1997	1.194
1998	1.272
1999	1.162
2000	0.93