# North American Monsoon Reconstruction Data during the Holocene #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # Template Version 4.0 # Encoding: UTF-8 # NOTE: Please cite original publication, NOAA Landing Page URL, dataset and publication DOIs (where available), and date accessed when using downloaded data. # If there is no publication information, please cite investigator, study title, NOAA Landing Page URL, and date accessed. # # Description/Documentation lines begin with '#' followed by a space # Data lines have no '#' # # NOAA_Landing_Page: https://www.ncei.noaa.gov/access/paleo-search/study/36653 # Landing_Page_Description: NOAA Landing Page of this file's parent study, which includes all study metadata. # # Study_Level_JSON_Metadata: https://www.ncei.noaa.gov/pub/data/metadata/published/paleo/json/noaa-recon-36653.json # Study_Level_JSON_Description: JSON metadata of this data file's parent study, which includes all study metadata. # # Data_Type: Climate Reconstructions # # Dataset_DOI: 10.25921/dshb-ct57 # # Science_Keywords: Monsoon #--------------------------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/reconstructions/routson2022/routson2022-ltg.txt # Data_Download_Description: NOAA Template File; Western N. America Latitudinal Temperature Gradient Reconstruction Data # #--------------------------------------- # Contribution_Date # Date: 2022-07-22 #--------------------------------------- # File_Last_Modified_Date # Date: 2022-07-22 #--------------------------------------- # Title # Study_Name: North American Monsoon Reconstruction Data during the Holocene #--------------------------------------- # Investigators # Investigators: Routson, Cody; Erb, Michael; McKay, Nicholas #--------------------------------------- # Description_Notes_and_Keywords # Description: #--------------------------------------- # Publication # Authors: Routson, Cody C.; Erb, Michael P.; McKay, Nicholas P. # Published_Date_or_Year: 2022-08-28 # Published_Title: High latitude modulation of the Holocene North American monsoon # Journal_Name: Geophysical Research Letters # Volume: 49 # Edition: # Issue: 16 # Pages: # Report_Number: e2022GL099772 # DOI: 10.1029/2022GL099772 # Online_Resource: # Full_Citation: # Abstract: The North American monsoon (NAM) is an important source of rainfall to much of Mexico and southwestern United States. Westerly winds (westerlies) can suppress monsoon circulation and impact monsoon timing, intensity, and extent. Recent Arctic warming is reducing the temperature gradient between the equator and the pole, which could weaken the westerlies; however, the implications of these changes on the NAM are uncertain. Here we present a new composite index of the Holocene NAM. We find monsoon strength reached a maximum circa 7,000 years ago and has weakened since then. Proxy observations of temperature, hydroclimate and upwelling, along with model simulations, show that the NAM was modulated by the westerlies over the Holocene. If the observed Holocene pattern holds for current warming, a weaker meridional temperature gradient and weaker westerlies could lead to a stronger future NAM. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: National Science Foundation # Grant: AGS-2002328 #--------------------------------------- # Site_Information # Site_Name: Western and Central North America and Eastern Pacific # Location: Global # Northernmost_Latitude: 60 # Southernmost_Latitude: 15 # Easternmost_Longitude: -80 # Westernmost_Longitude: -140 # Elevation_m: #--------------------------------------- # Data_Collection # Collection_Name: WNAm LTG Routson2022 # First_Year: 11900 # Last_Year: 100 # Time_Unit: calendar year before present # Core_Length_m: # Parameter_Keywords: air temperature # Notes: #--------------------------------------- # Chronology_Information # Chronology: #--------------------------------------- # Variables # PaST_Thesaurus_Download_Resource: https://www.ncei.noaa.gov/access/paleo-search/skos/past-thesaurus.rdf # PaST_Thesaurus_Download_Description: Paleoenvironmental Standard Terms (PaST) Thesaurus terms, definitions, and relationships in SKOS format. # # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-var components: what, material, error, units, seasonality, data type, detail, method, C or N for Character or Numeric data) # ## age_BP age,,,calendar year before present,,climate reconstructions,,,N, ## LTG temperature,multiple proxies,,degree Celsius per degree latitude,,climate reconstructions,,,N,Latitudinal Temperature Gradient Reconstruction ## LTG_STDV temperature,multiple proxies,one standard deviation,degree Celsius per degree latitude,,climate reconstructions,,,N,Standard deviation uncertainty of the latitudinal temperature gradient reconstruction #------------------------ # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: NaN age_BP LTG LTG_STDV 100 -0.504906 0.005966 300 -0.501012 0.005183 500 -0.501083 0.00481 700 -0.504216 0.003745 900 -0.505188 0.003664 1100 -0.505082 0.003753 1300 -0.503374 0.003763 1500 -0.500962 0.003852 1700 -0.501266 0.003996 1900 -0.501458 0.004245 2100 -0.503239 0.004541 2300 -0.502229 0.004218 2500 -0.501062 0.004144 2700 -0.502394 0.004184 2900 -0.502465 0.004483 3100 -0.503477 0.004701 3300 -0.505415 0.004479 3500 -0.504282 0.004647 3700 -0.501534 0.004487 3900 -0.503261 0.004469 4100 -0.501671 0.004437 4300 -0.49942 0.004612 4500 -0.500928 0.004436 4700 -0.495959 0.004541 4900 -0.502684 0.004316 5100 -0.498696 0.004176 5300 -0.49795 0.004134 5500 -0.499649 0.004273 5700 -0.50064 0.004483 5900 -0.500691 0.004629 6100 -0.503004 0.004534 6300 -0.500608 0.004518 6500 -0.500339 0.00463 6700 -0.499987 0.00475 6900 -0.502044 0.004547 7100 -0.497771 0.004752 7300 -0.497758 0.004683 7500 -0.496925 0.00476 7700 -0.498572 0.004422 7900 -0.497713 0.004663 8100 -0.496798 0.004536 8300 -0.495852 0.004613 8500 -0.493754 0.004952 8700 -0.497767 0.004916 8900 -0.493069 0.004559 9100 -0.496353 0.004915 9300 -0.495564 0.005179 9500 -0.496614 0.005053 9700 -0.493615 0.005521 9900 -0.494838 0.005393 10100 -0.496633 0.005708 10300 -0.496268 0.005579 10500 -0.4964 0.005971 10700 -0.505825 0.006262 10900 -0.508162 0.006346 11100 -0.498283 0.006746 11300 -0.50544 0.006846 11500 -0.508602 0.006966 11700 -0.51338 0.007659 11900 -0.512681 0.007962