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GENERAL INFORMATION
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1. Title of Dataset:  The State of the North Pacific Jet and North Atlantic Jet in the Context of their Two Leading Modes of Variability


2. Authors: Andrew C. Winters


3. Contact information: andrew.c.winters@colorado.edu


4. Date of data collection: 09/30/2021


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SHARING/ACCESS INFORMATION
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1. Licenses/restrictions placed on the data: No restrictions


2. Links to publications that cite or use the data: Winters and Walker (2022, to be submitted to the Journal of Applied Meteorology and Climatology)


3. Links to other publicly accessible locations of the data:


4. Recommended citation for the data:


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DATA & FILE OVERVIEW
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1. File List:


   A. Filename: npj_cfsrpcs.tar

        
   B. Filename: NAJ_unfilteredpcs_250hPa_with_regime.out


2. Relationship between files: File A contains files that describe the principal components corresponding to the state of the North Pacific Jet within the NCEP CFSR during 1979–2020. File B describes the principal components corresponding to the state of the North Atlantic Jet within the NCEP CFSR during 1979–2019.


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METHODOLOGICAL INFORMATION
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The state of the North Pacific Jet is determined from the two leading empirical orthogonal functions (EOFs) of 250-hPa zonal wind anomalies during September–May 1979–2019 within the NCEP Climate Forecast System Reanalysis. The first principal component obtained from the EOF analysis describes how strongly extended or retracted the North Pacific Jet is, while the second principal component obtained from the EOF analysis describes how strongly poleward or equatorward shifted the North Pacific Jet is. The state of the North Atlantic Jet is determined identically, however, the two leading modes of variability are reversed in order. Namely, the first mode of North Atlantic Jet variability corresponds to a poleward or equatorward shift of the North Atlantic Jet, whereas the second mode of variability corresponds to an extension or retraction. For full details on this methodology the reader is referred to Winters et al. (2019a) or Winters and Walker (2022, in review).


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DATA-SPECIFIC INFORMATION FOR: npj_cfsrpcs.tar
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1. Number of variables: 42 files / 6 variables in each file

2. Number of dates: Each file ranges from the start of a cool season (Sept. 1) through the end of May of the following year (May 31). The only exception is cfsrpcs_1979_new.out, which only contains data from Jan. 2, 1979–May 31, 1979.

3. Variable List:
	A. Name: Date and North Pacific Jet Principal Components
	   Description: The format is Year, Month, Day, Hour (UTC), Principal Component 1, Principal Component 2

        B. Name: 
       	   Description:

4. Data codes (e.g., N/A = Not applicable):



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DATA-SPECIFIC INFORMATION FOR: NAJ_unfilteredpcs_250hPa_with_regime.out
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1. Number of variables: 7

2. Number of Dates: All time steps between Jan 2, 1979–Dec. 30, 2019 that fall during the cool season (Sept–May) are included

3. Variable List:
	A. Name: Date and North Atlantic Jet Principal Components
	   Description: The format of is Year, Month, Day, Hour (UTC), Principal Component 2, Principal Component 1, Jet regime (1 = extension, 2 = retraction, 3 = poleward shift, 4 = equatorward shift, 5 = origin)

        B. Name: 
       	   Description:

4. Data codes (e.g., N/A = Not applicable):