ICE COVER STUDY

Township of Madawaska Valley

Barry's Bay, Ontario, Canada

Latitude 45^o 23.5' Longitude 77^o 38.5'

This small (~1 km2) land-locked lake is largely spring fed with no above-ground exit and is sheltered from heavy winds.
The Lake level is relatively constant, varying with weather and the seasons rather than with any flood-control program.
The ice generally melts in place rather than being pushed ashore, so the freeze and thaw is more directly dependent on temperature
than is the case with larger lakes exposed to more variables.

The slope now shows the ice cover per year to be receding at a rate of about 1 day per year;
however, in 1997, the trend actually indicated increasing ice cover days.
More significant perhaps, is the trend toward more chaotic behavior in the last half of the sample.

doug@dougdelamatter.com

For more data on more lakes see the Environment Canada site
(EMAN section "IceWatch") http://www.naturewatch.ca

Year	Freeze Over		Thawed		Ice Covered	Ice Free
	Date	Julian Day	Date	Julian Day	Days	Days

1980	23-Nov	328
1981	30-Nov	334	5-Apr	95	132	239
1982	11-Dec	345	27-Apr	117	148	228
1983	6-Dec	340	24-Apr	114	134	226
1984	5-Dec	340	21-Apr	112	137	228
1985	4-Dec	338	24-Apr	114	139	224
1986	1-Dec	335	7-Apr	97	124	238
1987	17-Dec	351	12-Apr	102	132	249
1988	9-Dec	334	13-Apr	104	118	240
1989	24-Nov	328	21-Apr	111	132	217
1990	11-Dec	345	20-Apr	110	147	235
1991	5-Dec	339	10-Apr	100	120	239
1992	6-Dec	341	3-May	124	115	217
1993	26-Nov	330	25-Apr	115	139	215
1994	16-Dec	350	18-Apr	108	143	242
1995	9-Dec	343	2-Apr	92	107	251
1996	25-Nov	330	27-Apr	118	140	212
1997	20-Dec	354	27-Apr	117	152	237
1998	1-Dec	335	13-Apr	103	114	232
1999	18-Dec	352	12-Apr	102	132	250
2000	3-Dec	338	2-Apr	93	106	245
2001	26-Dec	360	19-Apr	109	136	251
2002	28-Nov	332	12-Apr	102	107	230
2003	3-Dec	337	16-Apr	104	137	233
2004	6-Dec	341	17-Apr	108	136	233
2005	6-Dec	340	22-Apr	112	136	228
2006	28-Dec	362	14-Apr	104	129	258
2007	11-Dec	345	16-Apr	106	109	239
2008	6-Dec	341	21-Apr	112	132	229
2009			12-Apr	102	126