# Northeastern USA Little Ice Age Temperature and Precipitation Reconstructions #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #----------------------------------------------------------------------- # Template Version 2.0 # 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: https://www.ncdc.noaa.gov/paleo/study/6221 # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/pollen/recons/liadata.txt # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/pollen/recons/hells1988.txt # # Original_Source_URL: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Climate Reconstructions # # Parameter_Keywords: air temperature, precipitation #-------------------- # Contribution_Date # Date: 1993-01-04 #-------------------- # Title # Study_Name: Northeastern USA Little Ice Age Temperature and Precipitation Reconstructions #-------------------- # Investigators # Investigators: Gajewski, K. #-------------------- # Description_and_Notes # Description: Mean summer (JJA) temperatures and total annual precipitation for the past 2000 years # reconstructed from pollen from lakes with laminated sediments. The laminations ensure a more precise # time control than normally obtained from radiocarbon. #-------------------- # Publication # Authors: K. Gajewski # Published_Date_or_Year: 1988-05-01 # Published_Title: Late holocene climate changes in eastern North America estimated from pollen data # Journal_Name: Quaternary Research # Volume: 29 # Edition: # Issue: 3 # Pages: 255-262 # Report_Number: # DOI: 10.1016/0033-5894(88)90034-8 # Online_Resource: http://www.sciencedirect.com/science/article/pii/0033589488900348 # Full_Citation: # Abstract: Well-dated pollen profiles from six sites from Maine to Minnesota record vegetation changes indicative of summer temperature and annual precipitation variations over the past 2000 yr. Laminations in the sediment provide accurate time control. Multiple regression techniques were used to calculate calibration functions from a spatial network of modern pollen and climate data. When applied to the six pollen diagrams, these calibration functions yielded estimates that show a long-term trend toward lower summer temperature. Superimposed on this long-term trend are short-term fluctuations that are frequently in phase at the sites. Departures from the long-term cooling trend are positive around 1500 yr ago (indicating relative warmth) and negative between 200 and 500 yr ago (indicating relative cold). Annual precipitation showed a slight increase at several sites during the past 1000 yr relative to the previous 1000 yr. #------------------ # Publication # Authors: K. Gajewski # Published_Date_or_Year: 1987-01-01 # Published_Title: Climatic impacts on the vegetation of eastern North America during the past 2000 years # Journal_Name: Plant Ecology (formerly Vegetatio) # Volume: 68 # Edition: # Issue: 3 # Pages: 179-190 # Report_Number: # DOI: 10.1007/BF00114719 # Online_Resource: http://link.springer.com/article/10.1007/BF00114719 # Full_Citation: # Abstract: Pollen diagrams from seven lakes with annually laminated sediments sampled at 40-year intervals are analyzed to isolate the climatic effects from other effects on the long-term dynamics of vegetation during the past 1000-2000 years along a transect from Maine to Minnesota. Principal components analysis is used to reduce the dimensionality of the pollen data. The pollen records from all lakes show long-term trends, medium frequency oscillations, and higher frequency fluctuations. The long-term trend is associated with the neoglacial expansion of the boreal forest. The mechanism causing this replacement is a change in frequency of air masses in the area. The medium-frequency oscillations are also associated with climate changes, the most recent of which is the 'Little Ice Age'. The climate-related mechanism causing the medium-frequency changes may be changes in disturbance frequency. The higher frequency fluctuations may also be related to disturbance. This analysis of pollen diagrams into time scales of variation has enabled the separation of climate from other factors affecting vegetation dynamics. By comparing the principal components across a transect of sites it proved possible to interpret the climatic effects on vegetation at most sites and not only at range boundaries and 'sensitive' sites. #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: ATM-8219079, ATM-7926039, ATM-7423041 #------------------ # Site_Information # Site_Name: Hell's Kitchen Lake # Location: North America>United States Of America>Minnesota # Country: United States Of America # Northernmost_Latitude: 46.11 # Southernmost_Latitude: 46.11 # Easternmost_Longitude: -89.42 # Westernmost_Longitude: -89.42 # Elevation: 488 m #------------------ # Data_Collection # Collection_Name: Hells1988LIA # Earliest_Year: 2040 # Most_Recent_Year: 10 # Time_Unit: Cal. Year BP # Core_Length: m # Notes: #------------------ # Chronology_Information # Chronology: # #---------------- # Variables # # Data variables follow 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_calBP age, , , calendar years before 1975AD, , , , ,N ## temp-JJA surface temperature, , , Deg C, June-July-August, climate reconstructions, , ,N ## precip precipitation, , , mm, annual, climate reconstructions, , ,N # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: # age_calBP temp-JJA precip 10 18.3 845 20 18.6 902 30 18.4 827 40 18.4 858 50 18.1 863 60 18.4 926 70 18.1 956 80 18.0 921 90 17.9 1009 100 18.3 992 110 17.9 918 120 17.6 919 140 18.0 905 150 18.4 999 170 18.5 973 180 18.3 931 200 17.7 885 210 18.2 969 250 18.1 965 280 18.3 905 310 18.0 913 350 17.9 918 380 17.9 913 390 18.1 952 410 18.0 956 430 18.0 958 450 18.1 997 470 18.3 933 510 18.4 968 530 18.0 925 550 18.1 888 590 18.1 901 630 17.9 912 670 17.8 909 690 18.2 948 710 17.8 893 750 18.2 932 790 18.2 937 830 17.9 934 860 18.0 978 900 18.1 928 960 17.9 919 1000 18.0 869 1020 18.1 858 1040 18.3 897 1100 18.1 855 1120 18.2 925 1140 18.5 869 1160 18.7 876 1180 18.2 855 1200 18.2 885 1220 18.4 894 1240 18.3 864 1260 18.3 874 1280 18.6 924 1300 18.7 866 1320 18.2 830 1360 18.3 889 1400 18.3 850 1440 18.2 835 1480 18.2 812 1520 18.5 846 1560 18.5 912 1600 18.4 897 1640 18.2 853 1680 18.3 900 1720 18.3 836 1760 18.3 831 1800 18.4 829 1840 18.3 863 1880 18.1 937 1920 18.6 838 1960 18.1 847 2000 18.6 889 2040 18.4 841