Cape Grim
Point in Tasmania, Australia
From Wikipedia, the free encyclopedia
Cape Grim, officially Kennaook / Cape Grim,[2] is the northwestern point of Tasmania, Australia. The Peerapper name for the cape is recorded as Kennaook.[3]
Kennaook / Cape Grim | |
|---|---|
Cape Grim, looking North. The Doughboys on the left, Trefoil Island in middle distance, Hunter Island and Three Hummock Island beyond to the right. | |
  Kennaook / Cape Grim | |
| Coordinates: 40°38′31″S 144°43′33″ECoordinates[1] | |
| Location | Tasmania, Australia |
| Offshore water bodies | Southern Indian Ocean Bass Strait |
It is the location of the Cape Grim Baseline Air Pollution Station and of the Cape Grim Air Archive[4] which is operated by the Australian Bureau of Meteorology[5] in a joint programme with the CSIRO. The station was established in 1976 and has been operating ever since. The data from Cape Grim have been used extensively in assessments of climate change and ozone depletion.[6]
Geography
Cape Grim's isolated geographic location makes it unique. The next land mass directly west of Cape Grim is not Africa, but the southern tip of Argentina. Winds that make their way to Cape Grim from Antarctica and the Indian Ocean hit no significant land mass. Air pollution values collected at Cape Grim are the closest attainable representation of a global average.[7]
Climate
Kennaook experiences an oceanic climate bordering on a Warm-summer Mediterranean climate (Köppen: Cfb/Csb)[8] The climate is highly influenced by the cape's position in the Roaring Forties. Hence, all months have recorded a wind gust speed exceeding 125 km/h (78 mph). The wettest recorded day was 2 February 1990 with 109.2 mm (4.30 in) of rainfall. Extreme temperatures ranged from 30.5 °C (86.9 °F) on 29 January 2009 to −0.4 °C (31.3 °F) on 25 July 1986.[9]
The Baseline Air Pollution Station also recorded climate data for temperature, precipitation and 3 pm conditions from 1985 to 2023.
| Climate data for Cape Grim BAPS (Comparison) (40.68°S 144.69°E) (94 m (308 ft) AMSL) (1985-2023) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 30.5 (86.9) |
29.0 (84.2) |
28.0 (82.4) |
25.4 (77.7) |
21.0 (69.8) |
17.0 (62.6) |
16.6 (61.9) |
18.3 (64.9) |
21.0 (69.8) |
21.9 (71.4) |
27.2 (81.0) |
27.0 (80.6) |
30.5 (86.9) |
| Mean daily maximum °C (°F) | 19.2 (66.6) |
19.6 (67.3) |
18.7 (65.7) |
16.6 (61.9) |
14.6 (58.3) |
13.1 (55.6) |
12.6 (54.7) |
12.7 (54.9) |
13.4 (56.1) |
14.5 (58.1) |
16.0 (60.8) |
17.5 (63.5) |
15.7 (60.3) |
| Mean daily minimum °C (°F) | 13.3 (55.9) |
13.8 (56.8) |
13.0 (55.4) |
11.5 (52.7) |
10.2 (50.4) |
8.9 (48.0) |
8.2 (46.8) |
8.1 (46.6) |
8.6 (47.5) |
9.3 (48.7) |
10.6 (51.1) |
11.9 (53.4) |
10.6 (51.1) |
| Record low °C (°F) | 7.0 (44.6) |
8.0 (46.4) |
4.2 (39.6) |
4.9 (40.8) |
2.6 (36.7) |
0.0 (32.0) |
−0.4 (31.3) |
1.6 (34.9) |
3.0 (37.4) |
3.0 (37.4) |
4.1 (39.4) |
6.6 (43.9) |
−0.4 (31.3) |
| Average precipitation mm (inches) | 36.7 (1.44) |
34.2 (1.35) |
49.2 (1.94) |
63.8 (2.51) |
84.6 (3.33) |
84.6 (3.33) |
109.7 (4.32) |
102.8 (4.05) |
77.7 (3.06) |
65.9 (2.59) |
53.0 (2.09) |
44.1 (1.74) |
803.3 (31.63) |
| Average precipitation days (≥ 0.2 mm) | 11.1 | 10.3 | 14.4 | 17.9 | 21.4 | 21.5 | 24.0 | 24.1 | 22.0 | 18.9 | 14.8 | 13.4 | 213.8 |
| Average afternoon relative humidity (%) | 69 | 68 | 69 | 72 | 75 | 76 | 75 | 74 | 72 | 70 | 71 | 69 | 72 |
| Average dew point °C (°F) | 11.4 (52.5) |
12.0 (53.6) |
11.1 (52.0) |
9.8 (49.6) |
8.8 (47.8) |
7.6 (45.7) |
6.9 (44.4) |
6.7 (44.1) |
6.8 (44.2) |
7.4 (45.3) |
9.1 (48.4) |
10.0 (50.0) |
9.0 (48.1) |
| Source: Bureau of Meteorology (1985-2023)[10] | |||||||||||||
A newer weather station opened in 2010. It records climate data for temperature and precipitation.[11]
| Climate data for Kennaook (40.68°S 144.69°E) (86 m (282 ft) AMSL) (2010-2025) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °C (°F) | 30.0 (86.0) |
27.6 (81.7) |
26.3 (79.3) |
25.3 (77.5) |
20.3 (68.5) |
16.9 (62.4) |
16.3 (61.3) |
17.4 (63.3) |
20.7 (69.3) |
21.7 (71.1) |
23.4 (74.1) |
26.3 (79.3) |
30.0 (86.0) |
| Mean daily maximum °C (°F) | 19.7 (67.5) |
19.7 (67.5) |
18.9 (66.0) |
16.7 (62.1) |
14.5 (58.1) |
13.0 (55.4) |
12.5 (54.5) |
12.6 (54.7) |
13.3 (55.9) |
14.3 (57.7) |
15.7 (60.3) |
17.5 (63.5) |
15.7 (60.3) |
| Mean daily minimum °C (°F) | 13.8 (56.8) |
13.9 (57.0) |
13.3 (55.9) |
11.7 (53.1) |
10.2 (50.4) |
8.8 (47.8) |
8.4 (47.1) |
8.2 (46.8) |
8.7 (47.7) |
9.3 (48.7) |
10.7 (51.3) |
12.1 (53.8) |
10.8 (51.4) |
| Record low °C (°F) | 8.4 (47.1) |
8.5 (47.3) |
3.9 (39.0) |
5.1 (41.2) |
2.4 (36.3) |
2.8 (37.0) |
2.7 (36.9) |
1.5 (34.7) |
3.0 (37.4) |
3.8 (38.8) |
4.6 (40.3) |
6.4 (43.5) |
1.5 (34.7) |
| Average precipitation mm (inches) | 37.7 (1.48) |
33.3 (1.31) |
58.5 (2.30) |
53.9 (2.12) |
93.6 (3.69) |
101.0 (3.98) |
121.3 (4.78) |
120.4 (4.74) |
81.3 (3.20) |
71.3 (2.81) |
61.2 (2.41) |
43.4 (1.71) |
876.9 (34.52) |
| Average precipitation days (≥ 0.2 mm) | 9.9 | 9.6 | 14.9 | 17.9 | 22.3 | 21.4 | 23.5 | 24.1 | 20.8 | 18.3 | 16.6 | 13.6 | 212.9 |
| Source: Bureau of Meteorology (2010-2025)[12] | |||||||||||||
History
The headland was first charted and named Cape Grim by Matthew Flinders on 7 December 1798, as he sailed from the east in Norfolk and found a long swell coming from the south-west, confirming for the first time that Van Diemen's Land was separated from the Australian mainland by a strait, which he named Bass Strait.[13]
In 1828, Victory Hill at Cape Grim was the site of the Cape Grim massacre of thirty Peerapper people by four shepherds.[14]
