;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;Written by Brenda Dolan					;;;
;;;			  Colorado State University		;;;
;;;			  bdolan@atmos.colostate.edu	;;;
;;;			  June 20, 2012					;;;
;;;			  V1.0							;;;
;;;		Please email me if you see any		;;;
;;;	problems or have any comments on the HID;;;
;;; It is currently in a preliminary form   ;;;
;;; and we are in the process of validating ;;;
;;; it!										;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
The CSU Hydrometeor Identification Algorithm (HID) was developed from scattering simulations of different hydrometeor types (Dolan and Rutledge, 2009).  Recently, three categories were added from the Dolan and Rutledge (2009) study: Hail, wet snow, and big drops. The parameters for these simulations can be found in a forthcoming paper by Dolan et al., (2012). The HID uses 1D membership beta functions in a fuzzy logic framework.  The categories are the most probably hydrometeor type within a given volume.  The HID uses inputs from Reflectivity (CZ), Differential Reflectivity (DR), specific differentila phase (Kdp) and correlation coefficient (rhohv).  Additionally, temperature information is added using a local sounding.  In the case of NPOL data from MC3E, the closest sounding (+/- 6 hrs) from LMN was used.Note: On May 24, there were extra soundings at 18Z and 21Z.

The CSU Hydrometeor Identification Algorithm (HID) was applied to the NASA_QC'ed UF files. The HID field was written out to the 'FH' field in the mc3e_npol_2011mmdd_hhmm_hid.uf files. The other fields in this file are documented in the MC3E_NPOL_Data_Contents.pdf document.  

The HID consists of 10 categories identified by a number:

Number -> Short name -> Hydrometeor Type
0: -> UC -> Unclassified
1: -> DZ -> Drizzle
2: -> RN -> Rain
3: -> CR -> Ice Crystals
4: -> DS -> Dry Snow
5: -> WS -> Wet Snow
6: -> VI -> Vertically aligned ice (usually due to negative Kdp values; crystals that might be oriented due to a strong electric field)
7: -> DG -> Low Density Graupel ("Dry Graupel")
8: -> WG -> High Density Graupel ("Wet Graupel")
9: -> HA -> Hail
10:-> BD -> Big Drops


Notes: 
-Because there is some temperature input from the local sounding, some rain and drizzle may be identified above the wet snow because the radar identified melting layer (wet snow) may be lower than the sounding in places. 
-Keep in mind HID can be a bit noisy when run on radial data -- there may be some rogue wet graupel (e.g. due to low rhohv points), or big drops (if Zdr points are high, etc.)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;PLotting the data;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

For anyone using rsl_in_idl to plot the data, I added the following to plot the FH data for this HID:

;rsl_loadcolortable.pro
;-> under the rsl_mapcolors function:

   'FH': begin
	maxval = 10.
	minval = 0.
        color_bin_size = 1. ; mm/hr
	ncolors = (maxval - minval) / color_bin_size + 1.
	color_offset = 1. ; 0 is reserved for black.
	coloray = long(range/color_bin_size + color_offset)
	s = where(range lt 0.) ; 0. or missing value
	if size(s,/n_dimensions) gt 0 then coloray[s] = 0
	s = where(range gt maxval)
	if size(s,/n_dimensions) gt 0 then coloray[s] = ncolors
    end

;->under the main rsl_loadcolortable.pro program:

    'FH': begin
    print,'Using FHT colors!'
;				[	UC,		DZ		RN		CR		DS		WS		VI		DG		WG			HA		BD]
      r[0:11]= [0,	43,		135,	 0,		255,	232,	43,		153,	0,		255,		255,	239]
      g[0:11]= [0,	159,	35,		82,		138,	159,	255,	153,	241,	253,		0,		0]
      b[0:11]= [0,	165,	255,   227,		0,		185,	237,	153,	1,		0,			0,		255]
    end


;under rsl_colorbar.pro:

   'FH': begin
       labels = ['BD','HA','WG','DG','VI','WS','DS','CR','RN','DZ','UC'] 
       units = ''
    end