# 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/clear1988.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: Clear Pond # Location: North America>United States Of America>New York # Country: United States Of America # Northernmost_Latitude: 43.0 # Southernmost_Latitude: 43.0 # Easternmost_Longitude: -74.0 # Westernmost_Longitude: -74.0 # Elevation: m #------------------ # Data_Collection # Collection_Name: Clear1988LIA # Earliest_Year: 1890 # 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 18.4 1023 50 18.4 1005 90 19.1 1042 130 18.4 1055 170 18.9 1055 210 18.7 1050 250 18.6 1095 290 19.0 1053 330 18.2 1082 370 18.5 1101 410 18.9 1071 450 19.2 1032 490 18.9 1096 530 18.5 1086 570 18.8 1074 610 19.4 1036 650 19.1 1074 690 18.8 1095 730 18.4 1102 770 18.9 1093 810 18.6 1086 850 18.9 1074 890 18.8 1081 930 19.0 1090 970 19.4 1091 1010 18.5 1101 1050 19.3 1036 1090 19.5 1053 1130 19.8 1063 1170 19.2 1047 1210 19.0 1062 1250 19.5 1054 1290 19.8 1036 1330 20.1 1039 1370 20.8 1024 1410 19.7 1046 1450 19.8 1029 1490 19.9 1063 1530 20.3 1065 1570 19.9 1069 1610 20.1 1068 1650 19.2 1073 1690 19.5 1076 1730 19.7 1089 1770 19.3 1019 1810 20.2 1077 1850 19.8 1040 1890 20.2 1071