# northamerica_usa_ak016 - Exit Glacier - 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:
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# Online_Resource: https://www.ncdc.noaa.gov/paleo/study/24611
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# Original_Source_URL:https://www.ncdc.noaa.gov/paleo/study/5241
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# Description/Documentation lines begin with #
# Data lines have no #
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# Archive: Tree Rings
#--------------------
# Contribution_Date
#	Date: 2016-01-07
#--------------------
# Title
#	Study_Name: northamerica_usa_ak016 - Exit Glacier - 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 VaganovÃÂ¢ÃÂÃÂShashkin 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 4ÃÂ¢ÃÂÃÂ6 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 modelÃÂ¢ÃÂÃÂs 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.
#--------------------
#	Authors: Anderson, D.M., Tardif, R., Horlick, K., Erb, M.P., Hakim, G.J., Noone, D., Perkins, W.A., and E. Steig
#	Published_Date_or_Year: 2018
#	Published_Title: Additions to the last millennium reanalysis multi-proxy database
#	Journal_Name: Data Science Journal
#	Volume:
#	Edition:
#	Issue:
#	Pages:
#	Report_Number:
#	DOI:
#	Online_Resource:
#	Full_Citation: Anderson, D.M., Tardif, R., Horlick, K., Erb, M.P., Hakim, G., J., Noone, D., Perkins, W.A., and E. Steig, submitted. Additions to the last millennium reanalysis multi-proxy database. Data Science Journal.
#	Abstract: Progress in paleoclimatology increasingly occurs via data syntheses. We describe additions to a collection prepared for use in paleoclimate state estimation, specifically the Last Millennium Reanalysis (LMR).  The 2290 additional series include 2152 tree ring chronologies and 138 other series.  They supplement the collection used previously and together form a database titled LMRdb 1.0.0. The additional data draws from lake core, ice core, coral, speleothem, and tree ring archives, using published data primarily from the NOAA Paleoclimatology archive and a set of tree ring width chronologies standardized from raw International Tree Ring Data Bank ring width series. In contrast to many previous paleo compilations, the data were not selected (screened) on the basis of their environmental correlation, multi-century length, or other attributes. The inclusion of proxies sensitive to moisture and other environmental variables expands their use in data assimilation.  A preliminary calibration using linear regression with mean annual temperature reveals characteristics of the proxy series and their relationship to temperature, as well as the noise and error characteristics of the records. The additional records are structured as individual files in the NOAA Paleoclimatology format and archived at NOAA Paleoclimatology (Anderson et al. 2018) and will continue to be improved and expanded as part of the LMR Project.  The additions represent a four-fold increase in the number of records available for assimilation, provide expanded geographic coverage, and add additional proxy variables.  Applications include data assimilation, proxy system model development, and paleoclimate reconstruction using climate field reconstruction and other methods.
#------------------
# Funding_Agency
#	Funding_Agency_Name: Swiss National Science Foundation
#	Grant:
#--------------------
#	Funding_Agency_Name: National Science Foundation
#	Grant:AGS-1304263
#	Funding_Agency_Name: National Oceanic and Atmospheric Administration
#	Grant:NA14OAR4310176
#------------------
# Site_Information
#	Site_Name: Exit Glacier
#	Location:
#	Country: United States
#	Northernmost_Latitude: 60.2
#	Southernmost_Latitude: 60.2
#	Easternmost_Longitude: -149.58
#	Westernmost_Longitude: -149.58
#	Elevation: 480 m
#--------------------
# Data_Collection
#	Collection_Name: northamerica_usa_ak016B
#	Earliest_Year: 1658
#	Most_Recent_Year: 1988
#	Time_Unit: y_ad
#	Core_Length:
#	Notes: {"database":{"database1":"LMR","database2":"Breits"}} {"climateInterpretation":{"basis":"", "climateVariable":"T", "climateVariableDetail":"air", "interpDirection":"positive", "seasonality":"[6, 7, 8]"}}{"VSLite_parameters":{"T1":"4.74046286914","T2":"16.9654116751","M1":"0.0228110883609","M2":"0.392423133153"}}
#--------------------
# Species
#	Species_Name: Sitka spruce
#	Species_Code: PCSI
#--------------------
# Chronology:
#
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#
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# 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
1658	1.245
1659	1.231
1660	1.289
1661	1.078
1662	0.965
1663	0.842
1664	0.78
1665	0.753
1666	0.802
1667	0.89
1668	0.721
1669	0.96
1670	1.174
1671	1.243
1672	1.014
1673	1.163
1674	1.05
1675	1.094
1676	0.78
1677	0.495
1678	0.614
1679	0.524
1680	0.626
1681	0.66
1682	0.98
1683	1.209
1684	1.013
1685	1.337
1686	1.398
1687	1.324
1688	1.447
1689	1.096
1690	1.103
1691	1.024
1692	1.099
1693	0.944
1694	0.86
1695	0.937
1696	0.852
1697	0.505
1698	0.366
1699	0.428
1700	0.395
1701	0.847
1702	0.85
1703	1.083
1704	1.006
1705	1.014
1706	0.882
1707	1.064
1708	0.979
1709	0.993
1710	1.035
1711	0.671
1712	1.154
1713	1.173
1714	1.012
1715	1.031
1716	0.433
1717	0.398
1718	0.646
1719	0.789
1720	1.19
1721	1.228
1722	1.35
1723	1.203
1724	1.098
1725	1.239
1726	1.247
1727	1.329
1728	1.394
1729	1.229
1730	1.229
1731	1.38
1732	1.033
1733	0.754
1734	0.841
1735	1.068
1736	0.943
1737	1.111
1738	1.029
1739	1.244
1740	1.277
1741	0.907
1742	0.736
1743	0.869
1744	0.62
1745	0.585
1746	0.401
1747	0.61
1748	0.745
1749	1.058
1750	1.248
1751	1.068
1752	0.681
1753	0.534
1754	0.468
1755	0.518
1756	0.484
1757	0.574
1758	0.679
1759	0.558
1760	0.56
1761	0.527
1762	0.699
1763	0.795
1764	1.024
1765	0.961
1766	0.874
1767	0.899
1768	0.901
1769	1.19
1770	0.958
1771	0.595
1772	0.852
1773	0.964
1774	1.264
1775	0.92
1776	1.098
1777	1.436
1778	1.158
1779	1.159
1780	1.266
1781	0.841
1782	0.925
1783	1.03
1784	1.273
1785	1.237
1786	1.144
1787	1.026
1788	1.03
1789	1.077
1790	0.946
1791	1.066
1792	1.376
1793	1.093
1794	1.245
1795	1.682
1796	1.574
1797	1.728
1798	1.351
1799	1.079
1800	0.842
1801	0.92
1802	0.799
1803	0.727
1804	0.857
1805	0.941
1806	1.084
1807	1.091
1808	1.165
1809	0.877
1810	0.775
1811	0.658
1812	0.637
1813	0.537
1814	0.496
1815	0.683
1816	0.893
1817	0.843
1818	0.888
1819	0.989
1820	1.103
1821	1.065
1822	1.131
1823	1.16
1824	1.104
1825	1.236
1826	1.001
1827	0.961
1828	1.133
1829	1.335
1830	1.01
1831	0.729
1832	1.09
1833	1.087
1834	0.997
1835	0.991
1836	0.971
1837	0.675
1838	1.148
1839	1.06
1840	1.08
1841	1.169
1842	0.801
1843	0.8
1844	1.051
1845	1.031
1846	1.114
1847	1.087
1848	0.921
1849	0.64
1850	0.632
1851	0.827
1852	1.073
1853	1.04
1854	0.942
1855	0.911
1856	0.772
1857	0.906
1858	0.967
1859	0.98
1860	0.911
1861	0.923
1862	0.84
1863	0.981
1864	0.918
1865	0.902
1866	0.961
1867	1.037
1868	1.036
1869	0.79
1870	0.803
1871	0.655
1872	0.909
1873	0.972
1874	1.047
1875	0.811
1876	0.553
1877	0.388
1878	0.498
1879	0.642
1880	0.664
1881	0.869
1882	0.746
1883	0.766
1884	1.043
1885	0.822
1886	0.854
1887	0.875
1888	0.975
1889	0.674
1890	0.771
1891	0.878
1892	1.088
1893	1.053
1894	0.568
1895	0.397
1896	0.476
1897	0.525
1898	0.655
1899	0.871
1900	0.888
1901	1.078
1902	1.116
1903	0.985
1904	0.734
1905	0.864
1906	0.752
1907	0.727
1908	0.871
1909	0.894
1910	0.77
1911	0.755
1912	0.662
1913	0.747
1914	0.835
1915	1.405
1916	0.99
1917	1.354
1918	1.341
1919	1.043
1920	1.172
1921	1.183
1922	1.095
1923	1.307
1924	1.239
1925	1.398
1926	1.654
1927	1.183
1928	0.879
1929	0.769
1930	0.955
1931	1.292
1932	1.5
1933	1.667
1934	1.701
1935	1.587
1936	1.395
1937	0.921
1938	0.982
1939	1.081
1940	1.305
1941	1.346
1942	1.644
1943	1.862
1944	1.512
1945	1.022
1946	1.172
1947	1.442
1948	1.448
1949	1.316
1950	1.183
1951	1.016
1952	0.928
1953	1.235
1954	1.091
1955	0.847
1956	0.911
1957	1.045
1958	0.739
1959	1.044
1960	0.975
1961	1.171
1962	1.087
1963	1.054
1964	1.045
1965	0.862
1966	0.853
1967	0.713
1968	0.914
1969	0.817
1970	0.889
1971	0.889
1972	0.642
1973	0.507
1974	0.652
1975	0.554
1976	0.624
1977	0.748
1978	0.746
1979	0.895
1980	0.619
1981	1.048
1982	0.948
1983	0.994
1984	0.942
1985	0.867
1986	0.783
1987	0.651
1988	0.86