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			 **   THE GEM MESSENGER   **
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						     Volume 4, Number 11
						     July 25, 1994

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REPORT ON 1994 SNOWMASS WORKSHOP - BOUNDARY LAYER CAMPAIGN -- Part I 
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       WG 1: RECONNECTION ELECTRIC FIELD AND MAGNETOPAUSE BOUNDARY 
			   NORMAL MAGNETIC FIELD
                  co-chairs: Larry Lyons and Nelson Maynard

I.  DURING THE SUMMER 1994 WORKSHOP, IT WAS DECIDED TO DIRECT OUR EFFORTS IN 
THREE SPECIFIC DIRECTIONS AS FOLLOW:

A.  Periods of good multi-instrument coverage of the dayside cusp region at ~13 
to 16 UT, with IMF available,:

    1.  Dates:  27 Jan. 1992;  29 Mar. 1992;  21 July 1992
    2.  Scientific goal:  Identify separatrix and 2-dimensional flow versus 
        time across and in vicinity of separatrix.
    3.  Plan:  Bring data in usable format to Dec. GEM meeting; have some 
        results by summer 1995 workshop.
    4.  Responsibilities:
		Study coordinator:  Lyons
		Goose Bay data:  Greenwald
		Halley Bay data:  Pinnock
		Sondrestrom data:  Blanchard

B.  Test separatrix identification techniques with dayside optical observations, 
DMSP, and radars.

    1.  Dates:  6-7 Jan. 1992;  14 Jan. 1994
    2.  Plan:  Bring data in usable format to Dec. GEM meeting; have some 
        results by summer 1995 workshop.
    3.  Organize 6-7 Dec. 1994 to maximize possibilities for separatrix 
        identification tests.
    4.  Responsibilities:
		Study coordinator:  Maynard
		Optical data:  Jacobsen, Smith
		Sondrestrom radar:  Blanchard

C.  Continue determinations of polar-cap convection patterns and estimates of 
separatrix and boundary locations for intervals of relative stable IMF.

    1.  Dates:  27-29 Jan. 1992;  20-21 July 1992; 12-13 Jan. 1989
    2.  Coordination:  Lu, Lyons

II.  COMMENTS REGARDING DATA FOR SPECIFIC INTERVALS:

A.  27-29 Jan. 1992

    1.  Lyons presented synoptic space weather maps for both polar ionospheres 
	for stable IMF intervals 1325 to 1715 UT on 1/27 and 22:45 on 1/27 to 
	4:05 UT on 1/28.  Near noon and nightside separatrix identifications seem
        clear.  Pre-noon and post-noon separatrix identifications are more difficult 
	and controversial. Comparison with model results should proceed. 
    2.  Hairston showed that convection reversals are stable from pass to pass 
	during 22:45 on 1/27 to 4:05 UT on 1/28 stable IMF interval. 
    3.  Siscoe noted the potential significance of the occurrence of substorms 
	during the period of stable convection patters. 
    4.  Onsager emphasized the need for models having accurate cusp locations. 
    5.  Greenwald noted excellent agreement between the AMIE convection results 
	for the 22:45 on 1/27 to 4:05 UT on 1/28 interval, which only used Goose
        Bay data from one time, and the Goose Bay measurements throughout this 
	interval.  He also showed that there good flow data from Goose Bay near 
	noon MLT on 27 Jan. 

B.  March 28-29, 1992:  

    1.  Lu presented TIGCM results with and without neutral winds.  She found the 
	winds to have about a 25% effect on Joule heating and about a 10%
        effect on field-aligned currents. 
    2.  Greenwald noted the good quality of the Goose bay data on 3/29.
    3.  Clauer noted that there are good poleward progression in the Greenland 
	magnetometer data on 3/29. 

C.  Jan.6-7, 1992:  Knipp said that AMIE results for 1/7 are forthcoming, and 
that they may also do AMIE for 1/6

D.  Aug. 2-3, 1991:  Clauer described westward flow channels associated with the
poleward progressions (that result from oscillations in the IMF By component). 

E.  July 21, 1992:  Exceptionally good opportunity for data analysis for this
period, because of simultaneous radar coverage near noon from Sondrestrom, Goose
Bay, and Halley Bay.  Also 3 DMSP satellites in operation 

    1.  Lu:  AMIE results available for this period, including stable IMF intervals
    2.  Smith will contact those with South Pole optical data.

F.  Nov. 23-26, 1992:  Nothing new presented

G.  March 17-18, 21,  1993:  

    1.  3/17: Observations near magnetic noon show conditions to be relatively 
        quiet.  Goose Bay shows no echoes near noon, but interesting effects in 
        the dusk to evening period.  Blanchard noted that good Sondrestrom radar 
        data is available from near noon. 
    2.  3/18:  Sondrestrom data from near noon available
    3.  3/21:  Good dayside Goose bay data with good IMF data, but no Sondrestrom 
	data from dayside.

H.  Jan. 11 - 14, 1994.  Jacobsen and Smith noted that there is simultaneous 
dayside/nightside optical data available


Larry Lyons  (Internet:  Lyons at dirac2.dnet.nasa.gov  SPAN:  Dirac2::Lyons) 
Nelson Maynard  (Internet:  Maynard at zicon.plh.af.mil  SPAN:  afglsc::Maynard)

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