Add clarifying statement to GSI page

Author: BBeltz1

chapters/gsi.Rmd

@@ -18,7 +18,12 @@ State of the Ecosystem - Mid-Atlantic (2019 (Different Methods), 2020+)
 ## Methods
 The methods used to calculate the Gulf Stream Index changed between 2019 and 2020 SOEs. The most recent methods and at the top with older methods below those.
 
-This gulf stream index is a position anomaly meaning the larger the value of the index the further north the northern wall of the Gulf Stream is for that year. 
+This gulf stream index is a position anomaly meaning the larger the value of the index the further north the northern wall of the Gulf Stream is for that year.
+
+### 2025 SOE Reports and Northeast US Ecosystem Indicator Catalog
+The Gulf Stream indices presented in our 2025 SOE products are described below:
+
+The T200-based Gulf Stream Index is calculated as the standardized first principal component time series from the empirical orthogonal function (EOF) analysis of the 200 m temperature time series at the 20 base points (selected along the climatological (1954-2018) 15°C isotherm at 200 m between 74° and 55°W; 1° longitudinal resolution) and it represents the meridional fluctuation of the Gulf Stream North Wall [82,84,85]. The T200-based Western Gulf Stream Index is calculated using the same method, except only selecting the western 10 base points (instead of all 20 base points between 74° and 55°W). It suggests the meridional shift of the western part of the Gulf Stream North Wall.
 
 ### Data sources
 Data used in this analysis come from Compernicus Marine Environment Monitoring Service [CMEMS - GLOBAL OCEAN GRIDDED L4 SEA SURFACE HEIGHTS AND DERIVED VARIABLES REPROCESSED (1993-ONGOING)](https://doi.org/10.48670/moi-00148)(Product ID: SEALEVEL_GLO_PHY_L4_MY_008_047).

packages.bib

@@ -10,8 +10,8 @@ @Manual{R-base
 @Manual{R-bookdown,
   title = {bookdown: Authoring Books and Technical Documents with R Markdown},
   author = {Yihui Xie},
-  year = {2024},
-  note = {R package version 0.41},
+  year = {2025},
+  note = {R package version 0.42},
   url = {https://github.com/rstudio/bookdown},
 }
 
@@ -36,7 +36,7 @@ @Manual{R-ecodata
   author = {Brandon Beltz and Andy Beet and Kimberly Bastille and Sean Hardison},
   note = {R package version 5.0.2},
   url = {https://noaa-edab.github.io/ecodata/},
-  year = {2024},
+  year = {2025},
 }
 
 @Manual{R-forcats,
@@ -82,16 +82,16 @@ @Manual{R-kableExtra
 @Manual{R-knitr,
   title = {knitr: A General-Purpose Package for Dynamic Report Generation in R},
   author = {Yihui Xie},
-  year = {2024},
-  note = {R package version 1.49},
+  year = {2025},
+  note = {R package version 1.50},
   url = {https://yihui.org/knitr/},
 }
 
 @Manual{R-lubridate,
   title = {lubridate: Make Dealing with Dates a Little Easier},
   author = {Vitalie Spinu and Garrett Grolemund and Hadley Wickham},
-  year = {2023},
-  note = {R package version 1.9.3},
+  year = {2024},
+  note = {R package version 1.9.4},
   url = {https://lubridate.tidyverse.org},
 }
 
@@ -106,8 +106,8 @@ @Manual{R-miniUI
 @Manual{R-purrr,
   title = {purrr: Functional Programming Tools},
   author = {Hadley Wickham and Lionel Henry},
-  year = {2023},
-  note = {R package version 1.0.2},
+  year = {2025},
+  note = {R package version 1.0.4},
   url = {https://purrr.tidyverse.org/},
 }
 

tech_doc.Rmd

@@ -3675,7 +3675,12 @@ State of the Ecosystem - Mid-Atlantic (2019 (Different Methods), 2020+)
 ## Methods
 The methods used to calculate the Gulf Stream Index changed between 2019 and 2020 SOEs. The most recent methods and at the top with older methods below those.
 
-This gulf stream index is a position anomaly meaning the larger the value of the index the further north the northern wall of the Gulf Stream is for that year. 
+This gulf stream index is a position anomaly meaning the larger the value of the index the further north the northern wall of the Gulf Stream is for that year.
+
+### 2025 SOE Reports and Northeast US Ecosystem Indicator Catalog
+The Gulf Stream indices presented in our 2025 SOE products are described below:
+
+The T200-based Gulf Stream Index is calculated as the standardized first principal component time series from the empirical orthogonal function (EOF) analysis of the 200 m temperature time series at the 20 base points (selected along the climatological (1954-2018) 15°C isotherm at 200 m between 74° and 55°W; 1° longitudinal resolution) and it represents the meridional fluctuation of the Gulf Stream North Wall [82,84,85]. The T200-based Western Gulf Stream Index is calculated using the same method, except only selecting the western 10 base points (instead of all 20 base points between 74° and 55°W). It suggests the meridional shift of the western part of the Gulf Stream North Wall.
 
 ### Data sources
 Data used in this analysis come from Compernicus Marine Environment Monitoring Service [CMEMS - GLOBAL OCEAN GRIDDED L4 SEA SURFACE HEIGHTS AND DERIVED VARIABLES REPROCESSED (1993-ONGOING)](https://doi.org/10.48670/moi-00148)(Product ID: SEALEVEL_GLO_PHY_L4_MY_008_047).