TY - JOUR
T1 - Unprecedented acceleration of winter discharge of Upper Yenisei River inferred from tree rings
AU - Panyushkina, Irina P.
AU - Meko, David M.
AU - Shiklomanov, Alexander
AU - Thaxton, Richard D.
AU - Myglan, Vladimir
AU - Barinov, Valentin V.
AU - Taynik, Anna V.
N1 - Funding Information:
Original content from this work may be used under the terms of the . Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Science Foundation of Russian Federation 19-14-00028 U.S. NSF Polar Office program 19-14-00028 yes � 2021 The Author(s). Published by IOP Publishing Ltd Creative Commons Attribution 4.0 license
Publisher Copyright:
© 2021 The Author(s). Published by IOP Publishing Ltd.
PY - 2021/12
Y1 - 2021/12
N2 - The Yenisei River is the largest contributor of freshwater and energy fluxes among all rivers draining to the Arctic Ocean. Modeling long-Term variability of Eurasian runoff to the Arctic Ocean is complicated by the considerable variability of river discharge in time and space, and the monitoring constraints imposed by a sparse gauged-flow network and paucity of satellite data. We quantify tree growth response to river discharge at the upper reaches of the Yenisei River in Tuva, South Siberia. Two regression models built from eight tree-ring width chronologies of Larix sibirica are applied to reconstruct winter (Nov-Apr) discharge for the period 1784-1997 (214 years), and annual (Oct-Sept) discharge for the period 1701-2000 (300 years). The Nov-Apr model explains 52% of the discharge variance whereas Oct-Sept explains 26% for the calibration intervals 1927-1997 and 1927-2000, respectively. This new hydrological archive doubles the length of the instrumental discharge record at the Kyzyl gauge and resets the temporal background of discharge variability back to 1784. The reconstruction finds a remarkable 80% upsurge in winter flow over the last 25 years, which is unprecedented in the last 214 years. In contrast, annual discharge fluctuated normally for this system, with only a 7% increase over the last 25 years. Water balance modeling with CRU data manifests a significant discrepancy between decadal variability of the gauged flow and climate data after 1960. We discuss the impact on the baseflow rate change of both the accelerating permafrost warming in the discontinuous zone of South Siberia and widespread forest fires. The winter discharge accounts for only one third of the annual flow, yet the persistent 25 year upsurge is alarming. This trend is likely caused by Arctic Amplification, which can be further magnified by increased winter flow delivering significantly more fresh water to the Kara Sea during the cold season.
AB - The Yenisei River is the largest contributor of freshwater and energy fluxes among all rivers draining to the Arctic Ocean. Modeling long-Term variability of Eurasian runoff to the Arctic Ocean is complicated by the considerable variability of river discharge in time and space, and the monitoring constraints imposed by a sparse gauged-flow network and paucity of satellite data. We quantify tree growth response to river discharge at the upper reaches of the Yenisei River in Tuva, South Siberia. Two regression models built from eight tree-ring width chronologies of Larix sibirica are applied to reconstruct winter (Nov-Apr) discharge for the period 1784-1997 (214 years), and annual (Oct-Sept) discharge for the period 1701-2000 (300 years). The Nov-Apr model explains 52% of the discharge variance whereas Oct-Sept explains 26% for the calibration intervals 1927-1997 and 1927-2000, respectively. This new hydrological archive doubles the length of the instrumental discharge record at the Kyzyl gauge and resets the temporal background of discharge variability back to 1784. The reconstruction finds a remarkable 80% upsurge in winter flow over the last 25 years, which is unprecedented in the last 214 years. In contrast, annual discharge fluctuated normally for this system, with only a 7% increase over the last 25 years. Water balance modeling with CRU data manifests a significant discrepancy between decadal variability of the gauged flow and climate data after 1960. We discuss the impact on the baseflow rate change of both the accelerating permafrost warming in the discontinuous zone of South Siberia and widespread forest fires. The winter discharge accounts for only one third of the annual flow, yet the persistent 25 year upsurge is alarming. This trend is likely caused by Arctic Amplification, which can be further magnified by increased winter flow delivering significantly more fresh water to the Kara Sea during the cold season.
KW - Arctic amplification
KW - Siberian rivers
KW - discharge tree-ring reconstruction
KW - water balance model
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U2 - 10.1088/1748-9326/ac3e20
DO - 10.1088/1748-9326/ac3e20
M3 - Article
AN - SCOPUS:85122570093
VL - 16
JO - Environmental Research Letters
JF - Environmental Research Letters
SN - 1748-9326
IS - 12
M1 - 125014
ER -