Nitrogen, phosphorus, and suspended-sediment loads and trends measured at the Chesapeake Bay Nontidal Network stations: Water years 1985-2020 (ver. 2.0, January 2023)
Dates
Start Date
1984-10-01
End Date
2020-09-30
Publication Date
2022-07-25
Revision
2023-01-06
Citation
Mason, C.A., Colgin, J.E., and Moyer, D.L., 2023, Nitrogen, phosphorus, and suspended-sediment loads and trends measured at the Chesapeake Bay Nontidal Network stations: Water years 1985-2020 (ver. 2.0, January 2023): U.S. Geological Survey data release, https://doi.org/10.5066/P96H2BDO.
Summary
Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Network (NTN) stations stations for the period 1985 through 2020. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment that was exported from each of the NTN watersheds and were estimated using the WRTDS method with Kalman filtering. To determine the trend in loads, the annual load results are flow normalized to integrate [...]
Summary
Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Network (NTN) stations stations for the period 1985 through 2020. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment that was exported from each of the NTN watersheds and were estimated using the WRTDS method with Kalman filtering. To determine the trend in loads, the annual load results are flow normalized to integrate out the year-to-year variability in river discharge. The trend in load is derived from the flow-normalized load timeseries and represents the change in load resulting from changes in sources, delays associated with storage or transport of historical inputs, and (or) implemented management actions. Four data tables are provided that describe nitrogen, phosphorus, and suspended-sediment conditions across the NTN: (1) Annual Loads, (2) Monthly Loads, (3) Trends in Annual Loads, and (4) Average Yield (mass per unit area). Additionally, essential WRTDS Input and Output files are provided. First posted: July 25, 2022 (available from author) Revised: January 2023 (version 2.0)
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NTN_1985-2020_Landing_ver.2.0.xml Original FGDC Metadata
View
10.77 KB
application/fgdc+xml
EGRETci_2.0.4.tar.gz
3.02 MB
application/x-gzip
EGRET_3.0.7.tar.gz
3.76 MB
application/x-gzip
R-4.1.3-win.exe
86.44 MB
application/x-msdownload
NTN Load and Trend Summary 2020_ver.2.0.pdf
4.01 MB
application/pdf
NTN2020_ver.2.0_Revision_Notes.txt
3.58 KB
text/plain
Purpose
The purpose of this data release is to provide datasets for 1985-2020 (1) Annual Loads, (2) Monthly Loads, (3) Long- (~1985-2020) and Short- (2011-2020) Term Trends, and (4) 10- (2011-2020) and 5- (2016-2020) Year Average Yields. Additionally, essential WRTDS Input and Output files are provided.
Revision 2.0 by Christopher A Mason on January 6, 2023. To review the changes that were made, see “NTN2020_ver.2.0_Revision_Notes.txt” in the attached files section.
