Readme File for the SPEAR Catalog

This catalogue was created by adapting Anthony Yeates' code found on github (https://github.com/antyeates1983/sharps-bmrs) and as described in the Solar Physics paper "How good is the bipolar approximation of active regions for surface flux transport?" (Solar Physics, 2020, 295, 119).

See the HMI Nugget titled "Introducing the SPEAR catalogue from HMI Data" at 
http://hmi.stanford.edu/hminuggets/ for more information about the catalogue than what is contained in this ReadMe file.  

The SPEAR Carrington Rotation data differ from the dataset produced by Yeates' original code by including all SHARP regions, regardless of their magnetic polarity balance, whereas the catalog produced by Yeates' required a polarity balance.

The selected quantities included in the catalogues differ as well. For example this catalogue includes the latitude and longitude of the positive and negative polarity region of the SHARP data, sum of the line of sight magnetic field of SHARP regions, etc., which were not included in the original Yeates' catalogue.   

Columns in the SPEAR data file are as follows: 

    SHARP - SHARP number region (note that a single SHARP region may contain multiple NOAA regions)
    NOAA - NOAA active region number for the SHARP 
    T-REC - time of observation (when SHARP crossed central meridian).
    Day - Day of HMI Mission (beginning May 1 2010)
    CarRot - Carrington Rotation number 
    Lat - latitude of the region centroid [in degrees]
    Lon - longitude of the region centroid [in degrees]
    Lat+ - latitude of the positive polarity region centroid [in degrees]
    Lon+ - longitude of the positive polarity region centroid [in degrees]
    Lat- - latitude of the negative polarity region centroid [in degrees]
    Lon- - longitude of the negative polarity region centroid [in degrees]
    MTOT - sum of absolute values of LoS magnetic field in the patch [in Weber]
    MPOS  - sum of the positive LoS magnetic field in the patch [in Weber]
    MNEG - sum of the negative LoS magnetic field in the patch [in Weber]
    Area - area of the bipolar region [in microHemispheres]
    Sep  - separation distance between positive and negative polarity centroids [in Mm]
    Tilt - tilt angle as determined from the flux weighted centroid position of + and - polarities [in degrees]

    
Columns will look like this will values underneath...
SHARP    NOAA    T-REC                Day    CarRot    Lat    Lon    Lat+    Lon+    Lat-    Lon-    MTOT        MPOS        MNEG        Area            Sep        Tilt    Bipole
#              #          Time                  Day    #            Deg    Deg    Deg    Deg      Deg    Deg      Weber        Weber        Weber      microHem    Mm        Deg    Gauss

Please use the provided python notebook, READ-SPEAR-CR.ipynb, to read in the data, parse the data into useful segments.  The notebook contains sample plotting routines.