DOI: 10.25921/9t4z-qz46
title: NOAA/WDS Paleoclimatology - Pederson - Tujyin Nars - PISY - ITRDB MONG037

description: In its continuing move toward resource independence, Mongolia has recently entered a new agricultural era. Large crop fields and center-pivot irrigation have been established in the last 10 years across Mongolia's "Breadbasket": the Bulgan, Selenge and Tov aimags of northcentral Mongolia. Since meteorological records are typically short and spatially diffuse, little is known about the frequency and scale of past droughts in this region. We use six chronologies from the eastern portion of the breadbasket region to reconstruct streamflow of the Yeruu River. These chronologies accounted for 60.8% of May-September streamflow from 1959 to 1987 and 74.1% from 1988 to 2001. All split, calibration-verification statistics were positive, indicating significant model reconstruction. Reconstructed Yeruu River streamflow indicates the 20th century to be wetter than the two prior centuries. When comparing the new reconstruction to an earlier reconstruction of Selenge River streamflow, representing the western portion of the breadbasket region, both records document more pluvial events of greater intensity during 20th century versus prior centuries and indicate that the recent decade of drought that lead to greater aridity across the landscape is not unusual in the context of the last 300 years. Most interestingly, variability analyses indicate that the larger river basin in the western breadbasket (the Selenge basin) experiences greater swings in hydroclimate at multi-decadal to centennial time scales while the smaller basin in the eastern portion of the breadbasket (the Yeruu basin) is more stable. From this comparison, there would be less risk in agricultural productivity in the eastern breadbasket region, although the western breadbasket region can potentially be enormously productive for decades at a time before becoming quite dry for an equally long period of time. These results indicate that farmers and water managers need to prepare for both pluvial conditions like those in the late-1700s, and drier conditions like those during the early and mid-1800s. Recent studies have indicated that cultures with plentiful resources are more vulnerable when these resources become diminished. Thus, the instrumental records of the 20th century should not be used as a model of moisture availability. Most importantly, the geographic mismatch between precipitation, infrastructure, and water demand could turn out to be particularly acute for countries like Mongolia, especially as these patterns can switch in space through time.
description: This collection of PISY raw ring widths were made by the authors listed above on deep deposit of sandy soil south-southeast of the town Sukhbaatar, Mongolia for the potential usage in a reconstruction of hydroclimate. The trees cored here were somewhat open grown at the time of sampling. However, much of the low density is likely due to an intense fire in the years prior to our sampling. There ihttps://nesdev.ncdc.noaa.gov/i/asfdcldr.gifs much evidence of fire in this landscape. Use with care. For example, detrending these series mostly requires detrending as would be performed of trees from forest interior or closed-canopy forests. There appears to be periods of suppression and release from several trees when they were young. Fire damage is also a likely contributor to ring width variation. NOAA Template Raw Measurements file added 2019-04-08.