Jämtland 900 Year Tree Ring MXD Temperature Reconstruction Gunnarson, B.E.; Linderholm, H.W.; Moberg, A. Gunnarson, B.E. Linderholm, H.W. Moberg, A. Air Temperature Reconstruction earth science/paleoclimate/climate reconstructions|tree ring (age,null,null,year Common Era,null,climate reconstructions|tree ring,null,null,N,null) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,null,degree Celsius,Apr-Sep,climate reconstructions|tree ring,filtered,null,N,based on latewood density; RCS method 30-yr filtered) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,null,degree Celsius,Apr-Sep,climate reconstructions|tree ring,null,null,N,based on latewood density; RCS method) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited|smoothed,null,N,30 year spline) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,null,degree Celsius,Apr-Sep,climate reconstructions|tree ring,filtered,null,N,based on latewood density; non-RCS 30-yr filtered) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,one standard error lower bound,degree Celsius,Apr-Sep,climate reconstructions|tree ring,null,null,N,based on latewood density; non-RCS method; Spline 30 year) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,one standard error upper bound,degree Celsius,Apr-Sep,climate reconstructions|tree ring,null,null,N,based on latewood density; non-RCS method; Spline 30 year) earth science/paleoclimate/tree ring (tree ring standardized growth index,null,null,null,null,tree ring,composited,null,N,null) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,one standard error upper bound,degree Celsius,Apr-Sep,climate reconstructions|tree ring,null,null,N,based on latewood density; RCS method; Spline 30 yr) earth science/paleoclimate/tree ring (age,null,null,year Common Era,null,tree ring,null,null,N,null) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,one standard error lower bound,degree Celsius,Apr-Sep,climate reconstructions|tree ring,null,null,N,based on latewood density; RCS method; Spline 30 yr) earth science/paleoclimate/climate reconstructions|tree ring (surface temperature,ring density,null,degree Celsius,Apr-Sep,climate reconstructions|tree ring,null,null,N,based on latewood density; non-RCS method) earth science/paleoclimate/reconstructions (Jämtland>LATITUDE >LONGITUDE ) Dendroclimatological sampling of Scots pine (Pinus sylvestris L.) has been made in the province of Jämtland, in the west-central Scandinavian mountains, since the 1970s. The tree-ring width (TRW) chronology spans several thousand years and has been used to reconstruct June-August temperatures back to 1632 bc. A maximum latewood density (MXD) dataset, covering the period ad 1107-1827 (with gap 1292-1315) was presented in the 1980s by Fritz Schweingruber. Here we combine these historical MXD data with recently collected MXD data covering ad 1292-2006 into a single reconstruction of April-September temperatures for the period ad 1107-2006. Regional curve standardization (RCS) provides more low-frequency variability than “non-RCS” and stronger correlation with local seasonal temperatures (51% variance explained). The MXD chronology shows a stronger relationship with temperatures than the TRW data, but the two chronologies show similar multi-decadal variations back to ad 1500. According to the MXD chronology, the period since ad 1930 and around ad 1150-1200 were the warmest during the last 900 years. Due to large uncertainties in the early part of the combined MXD chronology, it is not possible to conclude which period was the warmest. More sampling of trees growing near the tree-line is needed to further improve the MXD chronology. STUDY NOTES: Tree ring maximum density temperature reconstruction for AD 1100-2006 based on a combination of old historical data and new data. Dry dead wood covers the period AD 1107-1907 and living trees cover the period AD 1450-2006. No subfossil lake material is included in the MXD data. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Gunnarson, B.E. Investigator : Linderholm, H.W. Investigator : Moberg, A. 2012-12-19 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/13644 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/gunnarson2011mxd.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/gunnarson2011temp.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/gunnarson2011mxd.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/gunnarson2011temp.txt English https://www.ncdc.noaa.gov/paleo/study/13644 https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/gunnarson2011mxd.txt https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/gunnarson2011temp.txt Björn E. Gunnarson, Hans W. Linderholm, and Anders Moberg. 2011. Improving a tree-ring reconstruction from west-central Scandinavia: 900 years of warm-season temperatures. Climate Dynamics, Vol. 36, Issues 1-2, pp. 97-108. DOI: 10.1007/s00382-010-0783-5 START YEAR: 1107 AD * END YEAR: 2007 AD 13.15 62.21 13.6 62.31