N. Hemisphere Extra-Tropics 2,000yr Decadal Temperature Reconstruction
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               World Data Center for Paleoclimatology, Boulder
                                  and
                     NOAA Paleoclimatology Program
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NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!


NAME OF DATA SET: 
N. Hemisphere Extra-Tropics 2,000yr Decadal Temperature Reconstruction

LAST UPDATE: 8/2010 (Original receipt by WDC Paleo)
CONTRIBUTOR: Ljungqvist, F.C.  
IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2010-089 


WDC PALEO CONTRIBUTION SERIES CITATION: 
Ljungqvist, F.C.  2009.  
N. Hemisphere Extra-Tropics 2,000yr Decadal Temperature Reconstruction. 
IGBP PAGES/World Data Center for Paleoclimatology 
Data Contribution Series # 2010-089.    
NOAA/NCDC Paleoclimatology Program, Boulder CO, USA.


ORIGINAL REFERENCE: 
Ljungqvist, F.C. 2010. 
A new reconstruction of temperature variability in the extra-tropical 
Northern Hemisphere during the last two millennia.
Geografiska Annaler: Physical Geography, Vol. 92 A(3), pp. 339-351,
September 2010.  DOI: 10.1111/j.1468-0459.2010.00399.x 

ABSTRACT:
A new temperature reconstruction with decadal resolution, covering 
the last two millennia, is presented for the extratropical Northern 
Hemisphere (90-30°N), utilizing many palaeotemperature proxy records 
never previously included in any large-scale temperature reconstruction. 
The amplitude of the reconstructed temperature variability on centennial 
time-scales exceeds 0.6°C. This reconstruction is the first to show 
a distinct Roman Warm Period c. AD 1-300, reaching up to the 1961-1990 
mean temperature level, followed by the Dark Age Cold Period c. AD 300-
800. The Medieval Warm Period is seen c. AD 800–1300 and the Little Ice 
Age is clearly visible c. AD 1300-1900, followed by a rapid temperature 
increase in the twentieth century. The highest average temperatures 
in the reconstruction are encountered in the mid to late tenth century 
and the lowest in the late seventeenth century. Decadal mean temperatures 
seem to have reached or exceeded the 1961-1990 mean temperature level 
during substantial parts of the Roman Warm Period and the Medieval Warm 
Period. The temperature of the last two decades, however, is possibly 
higher than during any previous time in the past two millennia, although
this is only seen in the instrumental temperature data and not in the 
multi-proxy reconstruction itself. Our temperature reconstruction agrees 
well with the reconstructions by Moberg et al. (2005) and Mann et al. 
(2008) with regard to the amplitude of the variability as well as the 
timing of warm and cold periods, except for the period c. AD 300-800, 
despite significant differences in both data coverage and methodology. 


GEOGRAPHIC REGION: Northern Hemisphere extra-tropics (90–30°N) 
PERIOD OF RECORD: 0 - 1999 AD, decadal resolution 



DESCRIPTION: 
Multi-proxy temperature reconstruction for the extra-tropical Northern 
Hemisphere (90-30°N) during the last two millennia based on 30 
palaeotemperature proxy records with annual to multi-decadal resolution. 
Proxy types include historical documentary records, seafloor sediment records, 
lake sediment records, speleothem records, ice-core records, varved thickness 
sediment records, tree-ring width and maximum latewood density records. 
The reconstruction is presented as decadal anomalies in degrees C relative 
to the 1961–1990 reference period and provided with quantitative error bars. 

Table 1. All temperature proxy records from across the extra-tropical Northern Hemisphere (90–30°N) used in our multi-proxy temperature
reconstruction containing information such as geographical location, exact latitude and longitude, type of proxy, sample resolution,
season bias, period covered by each record, and reference to the original publication. The proxy records are listed according
to latitude from north to south. The geographical locations of the records are shown on the map in Fig. 1. Records marked with ‡ have
never previously been used in any hemispheric or global multi-proxy temperature reconstruction.

Proxy location                      Latitude       Longitude      Proxy type*    SampleRes.  SeasonBias     Period covered    Reference
‡ 1. Lower Murray Lake, N. Canada   81°21'N        69°32'W        V              Annual          Summer     1–1969            Cook et al. 2009
2. Devon Island, N.Canada           75°34'N        89°19'W        Ice-core d18O  5 years         Annual     1–1969            Fisher et al. 1983
‡ 3. Greenland stack                75°N–65°11'N   38°3'–43°82'E  Ice-core d18O  Annual          Annual     200–1969          Andersen et al.2006
4. Taimyr peninsula,N. Siberia      73°00'N        105°E          TRW            Annual          Summer     1–1989            Naurzbaev et al. 2002
5. Indigirka, NE. Siberia           70°32'N        148°9'E        TRW            Annual          Summer     1–1989            Moberg et al. 2005
‡ 6. Big Round Lake, Baffin Island  69°52'N        68°50'W        V              Annual          Summer     980–1999          Thomas and Briner2009
7. Lake Tsuolbmajavri, N.Fennoscand.68°41'N        22°03'E        Lf             Multi-dec/cent. Summer     1–1989            Korhola et al. 2000
‡ 8. Torneträsk, N. Fennoscandia    68°12'N        19°27°E        MXD            Annual          Summer     510–1999          Grudd 2008
9. Polar Urals, NW, Siberia         66°52'N        65.38°E        MXD            Annual          Summer     780–1989          Esper et al. 2002a
10. Donard Lake, Baffin Island      66°40'N        61°21'W        V              Annual          Summer     800–1989          Moore et al. 2001
‡ 11. North Iceland Shelf           66°33'N        17°42'W        Md             2–5 years       Summer     1–1949            Sicre et al. 2008
‡ 12. Haukadalsvatn, W. Iceland     65°03°N        21°38°W        Lf             Decadal         Spring/Sum.1–1999            Geirsdóttir et al.2009
‡ 13. Korallgrottan , C. Sweden     64°54'N        14°8'E         Sp             Multi-decadal   Annual     1–1999            Sundqvist et al. 2010
‡ 14. Jämtland, C. Sweden           63°10'N        12°25'–13°35'E TRW            Annual          Summer     1–870, 910–1999   Linderholm and Gunnarson 2005
‡ 15. Farewell Lake, C. Alaska      62°33'N        153°38'W       Lf             Multi-dec/cent. Summer     1–1959            Hu et al. 2001
16. Gulf of Alaska                  61°N           146°W          MXD            Annual          Summer     730–1999          D’Arrigo et al. 2006
‡ 17. Iceberg Lake, Alaska          60°47'N        142°57'W       Lf             Annual          Summer     450–1989          Loso 2009
18. Canadian Rockies                52.9°N         117.9°W        MXD            Annual          Summer     950–1989          Luckman and Wilson 2005
‡ 19. Spannagel Cave, C. Alps       47°05'N        11°40'E        Sp             1–10 years      Annual     1–1929            Mangini et al. 2005
20. The Alps                        47°00          7–13°E         MXD            Annual          Summer     760–1999          Büntgen et al. 2006
‡ 21. Lake Silvaplana, Switzerland  46°27'N        9°48'E         Lf             Annual to decad.Summer     980–1999          Larocque et al. 2009
‡ 22. E. China                      42°–27°N       110°–120°E     D              Decadal         Annual     20–1999           Yang et al. 2002
23. E. China                        40°–27°N       107°–120°E     D              Decadal         Winter     20–1999           Ge et al. 2003
24. Shihua Cave, Beijing, China     39°54'N        116°23'E       Sp             Annual          Summer     1–1979            Tan et al. 2003
25. Chesapeake Bay, E. USA          38°89'N        76°40'W        Md             Multi-decadal   Spring     1–1989            Cronin et al. 2003
‡ 26. Lake Qinghai, Tibetan Plateau 37°N           100°E          Lf             Multi-decadal   Annual     1–1939            Liu et al. 2006
‡ 27. NW. Karakorum                 37–35°N        74–76°E        TRW            Annual          Annual     620–1989          Esper et al. 2002b
‡ 28. Dulan, NE. Qinghai-Tibet.Plat.36°N           98°E           TRW            Annual          Annual     1–1999            Zhang et al. 2003
29. Bermuda Rise, Sargasso Sea      33°41'N        74°26'W        Md             Multi-dec/cent. Annual     1–1969            Keigwin 1996
‡ 30. Yakushima Island, S. Japan    30°20'N        130°30'E       Tree-ring d13C Decadal         Annual     130–1949          Kitagawa and Matsumoto 1995

Notes: * D, documentary; Lf, lake/river fossils and sediments; MXD, tree-ring maximum latewood density; Md, marine sediments; Sp,
speleothem isotopic analysis; TRW, tree-ring width; V, varved thickness sediments


DATA: 
Northern Hemisphere Extra-Tropics Temperature Reconstruction
As plotted in Figure 3, Ljungqvist (2010).
Missing data: 99.999.

Column 1: Decade AD
Column 2: Reconstructed temperature anomaly in degrees C with respect to 1961–1990
Column 3: Upper 2 standard deviation error bar
Column 4: Lower 2 standard deviation error bar
Column 5: Instrumental temperature data from the variance adjusted CRUTEM3+HadSST2 90–30°N data set

Decade      ReconT     Up.err.    Lo.err.   Inst.Temp. 
0–9         -0.065      0.056     -0.186     99.999
10–19       -0.041      0.090     -0.172     99.999
20–29       -0.094      0.055     -0.243     99.999
30–39       -0.059      0.094     -0.212     99.999
40–49        0.006      0.161     -0.150     99.999
50–59        0.106      0.289     -0.078     99.999
60–69        0.039      0.227     -0.149     99.999
70–79       -0.026      0.104     -0.156     99.999
80–89        0.054      0.173     -0.066     99.999
90–99       -0.021      0.112     -0.155     99.999
100–109     -0.023      0.134     -0.180     99.999
110–119     -0.022      0.105     -0.149     99.999
120–129     -0.044      0.076     -0.163     99.999
130–139      0.007      0.127     -0.113     99.999
140–149      0.023      0.144     -0.098     99.999
150–159      0.064      0.203     -0.076     99.999
160–169      0.114      0.287     -0.059     99.999
170–179      0.080      0.251     -0.090     99.999
180–189      0.050      0.244     -0.143     99.999
190–199     -0.040      0.102     -0.182     99.999
200–209     -0.077      0.090     -0.244     99.999
210–219     -0.150      0.010     -0.310     99.999
220–229     -0.043      0.103     -0.190     99.999
230–239     -0.118      0.039     -0.275     99.999
240–249     -0.094      0.025     -0.214     99.999
250–259     -0.100      0.020     -0.221     99.999
260–269     -0.231     -0.089     -0.373     99.999
270–279     -0.206     -0.064     -0.347     99.999
280–289     -0.216     -0.080     -0.352     99.999
290–299     -0.273     -0.153     -0.392     99.999
300–309     -0.288     -0.168     -0.408     99.999
310–319     -0.294     -0.174     -0.414     99.999
320–329     -0.407     -0.288     -0.527     99.999
330–339     -0.384     -0.264     -0.504     99.999
340–349     -0.391     -0.221     -0.561     99.999
350–359     -0.328     -0.156     -0.500     99.999
360–369     -0.207     -0.087     -0.326     99.999
370–379     -0.162      0.015     -0.340     99.999
380–389     -0.280     -0.157     -0.402     99.999
390–399     -0.311     -0.187     -0.434     99.999
400–409     -0.269     -0.150     -0.389     99.999
410–419     -0.201     -0.078     -0.324     99.999
420–429     -0.233     -0.096     -0.371     99.999
430–439     -0.311     -0.145     -0.477     99.999
440–449     -0.228     -0.081     -0.376     99.999
450–459     -0.346     -0.168     -0.524     99.999
460–469     -0.437     -0.259     -0.615     99.999
470–479     -0.417     -0.252     -0.582     99.999
480–489     -0.195     -0.018     -0.373     99.999
490–499     -0.317     -0.138     -0.496     99.999
500–509     -0.367     -0.188     -0.545     99.999
510–519     -0.438     -0.270     -0.606     99.999
520–529     -0.321     -0.154     -0.488     99.999
530–539     -0.455     -0.287     -0.623     99.999
540–549     -0.471     -0.298     -0.643     99.999
550–559     -0.254     -0.071     -0.437     99.999
560–569     -0.262     -0.108     -0.417     99.999
570–579     -0.195     -0.026     -0.364     99.999
580–589     -0.128      0.053     -0.310     99.999
590–599     -0.199     -0.024     -0.374     99.999
600–609     -0.182     -0.019     -0.345     99.999
610–619     -0.183     -0.024     -0.341     99.999
620–629     -0.275     -0.087     -0.463     99.999
630–639     -0.289     -0.101     -0.477     99.999
640–649     -0.296     -0.123     -0.469     99.999
650–659     -0.231     -0.039     -0.424     99.999
660–669     -0.194     -0.003     -0.386     99.999
670–679     -0.169      0.040     -0.377     99.999
680–689     -0.281     -0.091     -0.472     99.999
690–699     -0.273     -0.080     -0.467     99.999
700–709     -0.364     -0.197     -0.532     99.999
710–719     -0.289     -0.127     -0.452     99.999
720–729     -0.298     -0.138     -0.457     99.999
730–739     -0.236     -0.075     -0.396     99.999
740–749     -0.221     -0.072     -0.370     99.999
750–759     -0.274     -0.131     -0.418     99.999
760–769     -0.242     -0.122     -0.362     99.999
770–779     -0.281     -0.129     -0.432     99.999
780–789     -0.223     -0.093     -0.352     99.999
790–799     -0.241     -0.078     -0.404     99.999
800–809     -0.253     -0.110     -0.396     99.999
810–819     -0.162     -0.018     -0.307     99.999
820–829     -0.144     -0.013     -0.275     99.999
830–839     -0.020      0.162     -0.202     99.999
840–849      0.003      0.128     -0.123     99.999
850–859     -0.021      0.137     -0.180     99.999
860–869     -0.030      0.157     -0.216     99.999
870–879     -0.027      0.093     -0.148     99.999
880–889     -0.067      0.074     -0.207     99.999
890–899     -0.034      0.086     -0.154     99.999
900–909     -0.214     -0.078     -0.350     99.999
910–919     -0.119      0.042     -0.280     99.999
920–929     -0.112      0.035     -0.259     99.999
930–939     -0.024      0.096     -0.144     99.999
940–949      0.016      0.136     -0.103     99.999
950–959      0.196      0.377      0.015     99.999
960–969      0.172      0.292      0.052     99.999
970–979      0.048      0.171     -0.075     99.999
980–989      0.035      0.159     -0.088     99.999
990–999     -0.018      0.102     -0.138     99.999
1000–1009    0.016      0.135     -0.104     99.999
1010–1019    0.063      0.182     -0.057     99.999
1020–1029    0.106      0.231     -0.020     99.999
1030–1039    0.029      0.149     -0.091     99.999
1040–1049   -0.045      0.075     -0.165     99.999
1050–1059   -0.002      0.118     -0.122     99.999
1060–1069    0.006      0.128     -0.115     99.999
1070–1079   -0.059      0.060     -0.179     99.999
1080–1089    0.055      0.174     -0.065     99.999
1090–1099   -0.034      0.085     -0.154     99.999
1100–1109   -0.098      0.022     -0.218     99.999
1110–1119   -0.159     -0.039     -0.279     99.999
1120–1129   -0.142     -0.022     -0.262     99.999
1130–1139   -0.142     -0.022     -0.261     99.999
1140–1149   -0.140     -0.021     -0.260     99.999
1150–1159   -0.177     -0.039     -0.316     99.999
1160–1169   -0.144     -0.017     -0.272     99.999
1170–1179   -0.169     -0.049     -0.289     99.999
1180–1189   -0.157     -0.037     -0.277     99.999
1190–1199   -0.215     -0.096     -0.335     99.999
1200–1209   -0.146     -0.026     -0.265     99.999
1210–1219   -0.137     -0.017     -0.257     99.999
1220–1229   -0.123      0.010     -0.256     99.999
1230–1239   -0.164     -0.013     -0.314     99.999
1240–1249   -0.121      0.019     -0.262     99.999
1250–1259   -0.157     -0.037     -0.276     99.999
1260–1269   -0.197     -0.077     -0.317     99.999
1270–1279   -0.226     -0.107     -0.346     99.999
1280–1289   -0.262     -0.122     -0.401     99.999
1290–1299   -0.256     -0.128     -0.384     99.999
1300–1309   -0.196     -0.077     -0.316     99.999
1310–1319   -0.253     -0.134     -0.373     99.999
1320–1329   -0.344     -0.224     -0.463     99.999
1330–1339   -0.412     -0.293     -0.532     99.999
1340–1349   -0.336     -0.217     -0.456     99.999
1350–1359   -0.369     -0.249     -0.489     99.999
1360–1369   -0.290     -0.171     -0.410     99.999
1370–1379   -0.282     -0.163     -0.402     99.999
1380–1389   -0.293     -0.174     -0.413     99.999
1390–1399   -0.276     -0.156     -0.396     99.999
1400–1409   -0.228     -0.108     -0.347     99.999
1410–1419   -0.311     -0.191     -0.431     99.999
1420–1429   -0.399     -0.280     -0.519     99.999
1430–1439   -0.349     -0.230     -0.469     99.999
1440–1449   -0.436     -0.316     -0.557     99.999
1450–1459   -0.543     -0.409     -0.676     99.999
1460–1469   -0.486     -0.356     -0.617     99.999
1470–1479   -0.495     -0.375     -0.615     99.999
1480–1489   -0.564     -0.441     -0.686     99.999
1490–1499   -0.471     -0.351     -0.591     99.999
1500–1509   -0.360     -0.240     -0.480     99.999
1510–1519   -0.441     -0.312     -0.571     99.999
1520–1529   -0.493     -0.369     -0.617     99.999
1530–1539   -0.361     -0.241     -0.481     99.999
1540–1549   -0.439     -0.319     -0.558     99.999
1550–1559   -0.366     -0.244     -0.488     99.999
1560–1569   -0.375     -0.245     -0.504     99.999
1570–1579   -0.445     -0.325     -0.565     99.999
1580–1589   -0.490     -0.370     -0.609     99.999
1590–1599   -0.509     -0.389     -0.628     99.999
1600–1609   -0.608     -0.489     -0.728     99.999
1610–1619   -0.555     -0.435     -0.675     99.999
1620–1629   -0.535     -0.416     -0.655     99.999
1630–1639   -0.560     -0.440     -0.679     99.999
1640–1649   -0.622     -0.489     -0.754     99.999
1650–1659   -0.537     -0.405     -0.669     99.999
1660–1669   -0.586     -0.467     -0.706     99.999
1670–1679   -0.605     -0.469     -0.740     99.999
1680–1689   -0.675     -0.551     -0.798     99.999
1690–1699   -0.692     -0.572     -0.812     99.999
1700–1709   -0.609     -0.489     -0.729     99.999
1710–1719   -0.493     -0.366     -0.620     99.999
1720–1729   -0.326     -0.206     -0.446     99.999
1730–1739   -0.357     -0.237     -0.477     99.999
1740–1749   -0.374     -0.254     -0.493     99.999
1750–1759   -0.347     -0.227     -0.466     99.999
1760–1769   -0.309     -0.189     -0.428     99.999
1770–1779   -0.376     -0.256     -0.496     99.999
1780–1789   -0.406     -0.286     -0.525     99.999
1790–1799   -0.357     -0.237     -0.476     99.999
1800–1809   -0.341     -0.221     -0.461     99.999
1810–1819   -0.461     -0.341     -0.581     99.999
1820–1829   -0.351     -0.231     -0.471     99.999
1830–1839   -0.391     -0.267     -0.515     99.999
1840–1849   -0.327     -0.207     -0.446     99.999
1850–1859   -0.318     -0.199     -0.438     -0.224
1860–1869   -0.379     -0.253     -0.504     -0.284
1870–1879   -0.239     -0.102     -0.376     -0.228
1880–1889   -0.337     -0.217     -0.457     -0.308
1890–1899   -0.250     -0.130     -0.370     -0.290
1900–1909   -0.293     -0.162     -0.425     -0.378
1910–1919   -0.296     -0.176     -0.416     -0.379
1920–1929   -0.171     -0.041     -0.302     -0.156
1930–1939    0.004      0.156     -0.148      0.064
1940–1949    0.019      0.158     -0.120      0.042
1950–1959    0.037      0.157     -0.083     -0.003
1960–1969    0.015      0.135     -0.105     -0.044
1970–1979   -0.074      0.046     -0.194     -0.094
1980–1989    0.082      0.202     -0.038      0.082
1990–1999    0.056      0.197     -0.085      0.388


