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Title: Long-range dependence and extreme values of precipitation, phosphorus load, and Cyanobacteria
Extreme daily values of precipitation (1939–2021), discharge (1991–2021), phosphorus (P) load (1994–2021), and phycocyanin, a pigment of Cyanobacteria (June 1–September 15 of 2008–2021) are clustered as multi-day events for Lake Mendota, Wisconsin. Long-range dependence, or memory, is the shortest for precipitation and the longest for phycocyanin. Extremes are clustered for all variates and those of P load and phycocyanin are most strongly clustered. Extremes of P load are predictable from extremes of precipitation, and precipitation and P load are correlated with later concentrations of phycocyanin. However, time delays from 1 to 60 d were found between P load extremes and the next extreme phycocyanin event within the same year of observation. Although most of the lake’s P enters in extreme events, blooms of Cyanobacteria may be sustained by recycling and food web processes.  more » « less
Award ID(s):
2025982
NSF-PAR ID:
10399288
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
119
Issue:
48
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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