It’s another mindless record used to remind the public to “keep the faith” and recite the litany:
“Adelaide had it’s hottest start to the year since 1900” Sky news
Picking three particular days outof 365 and comparing them over a century is about as cherry-pickingly meaningless as it gets. But Ian Hill went back through the records to find that not only have there been 79 heatwaves in Adelaide since 1887, but there have been 51 heat-waves that were hotter since 1887.
Ian Hill crunched the numbers and wrote:
Using the definition of a heatwave being “three or more consecutive days at or above 38C”, for no other reason than the fact that this fits in nicely with Adelaide’s recent maxima of 38.0, 41.6 and 40.6 on Dec 31, Jan 1 and Jan 2 respectively, I found that there have been 79 such heatwaves recorded in Adelaide since Jan 21, 1887, the date of the first such information available from the BOM. The recent heatwave is ranked 52nd, where the average maximum of days involved is used to rank heatwaves of the same duration.
If the file is sorted in chronological order a familiar trend emerges where there are many years on end with no heatwaves, then clusters of them. Between 1973 and 1989 there was only one, a week-long heatwave in January 1982. The longest heatwave was in March 2008 where there were 12 consecutive days above 38 degrees C. In fact the day before was 37.9 and the previous two days to that were above 35, so it was reported as a 15-day heatwave. This would be the true “record” for many sites in SE Australia and for Adelaide it was called “a once in 3000 years occurrence”.
Probably the most severe heatwaves were in January 1908 where the Adelaide citizens endured a week of temperatures averaging 43.2. Earlier in the month they had six days averaging 41.8.
The Adelaide data comes from two BOM sites, West Terrace until 1976 and then Kent Town, 2km to the east. As far as I’m concerned there’s not much difference between them for the purposes of this exercise.
Regards
Ian
UPDATE: Someone has taken this nice data and done good graphs of Adelaide Heatwaves.
—————————————
Heatwaves in Adelaide |
|||||
Definition: Three or more days at or above 38C | |||||
Observations: West Terrace site prior to 1977. Kent Town from 1977. | |||||
Date |
|||||
Rank |
Date ended |
Days |
Ave max |
order |
|
1 |
Mar 17, 2008 |
12 |
39.342 |
75 |
|
2 |
Jan 19, 1908 |
7 |
43.243 |
23 |
|
3 |
Feb 2, 2009 |
7 |
42.271 |
76 |
|
4 |
Jan 24, 1982 |
7 |
40.843 |
58 |
|
5 |
Mar 13, 1934 |
7 |
40.743 |
40 |
|
6 |
Mar 13, 1940 |
7 |
40.600 |
44 |
|
7 |
Jan 7, 1908 |
6 |
41.750 |
22 |
|
8 |
Jan 14, 1927 |
6 |
41.367 |
35 |
|
9 |
Feb 13, 1899 |
6 |
41.267 |
12 |
|
10 |
Jan 19, 1934 |
6 |
39.717 |
39 |
|
11 |
Feb 22, 1997 |
6 |
39.367 |
64 |
|
12 |
Nov 15, 2009 |
6 |
39.150 |
77 |
|
13 |
Jan 10, 1939 |
5 |
42.860 |
42 |
|
14 |
Dec 30, 1897 |
5 |
40.580 |
8 |
|
15 |
Feb 4, 1898 |
5 |
40.540 |
9 |
|
16 |
Feb 13, 1939 |
5 |
40.060 |
43 |
|
17 |
Jan 6, 1906 |
4 |
43.950 |
19 |
|
18 |
Feb 3, 1912 |
4 |
43.300 |
28 |
|
19 |
Jan 13, 1905 |
4 |
42.925 |
18 |
|
20 |
Jan 29, 1943 |
4 |
42.200 |
47 |
|
21 |
Jan 3, 1900 |
4 |
41.850 |
13 |
|
22 |
Jan 11, 2010 |
4 |
41.775 |
78 |
|
23 |
Jan 22, 2006 |
4 |
41.475 |
72 |
|
24 |
Jan 12, 1889 |
4 |
41.300 |
2 |
|
25 |
Mar 4, 1942 |
4 |
41.300 |
46 |
|
26 |
Jan 19, 1959 |
4 |
41.000 |
50 |
|
27 |
Jan 1, 2008 |
4 |
40.925 |
74 |
|
28 |
Dec 31, 1898 |
4 |
40.575 |
11 |
|
29 |
Jan 25, 1921 |
4 |
40.525 |
32 |
|
30 |
Jan 28, 1961 |
4 |
40.375 |
52 |
|
31 |
Feb 3, 1993 |
4 |
40.125 |
63 |
|
32 |
Jan 21, 1973 |
4 |
39.750 |
57 |
|
33 |
Feb 15, 1895 |
4 |
39.500 |
7 |
|
34 |
Jan 25, 2001 |
4 |
39.300 |
68 |
|
35 |
Mar 3, 1989 |
4 |
38.825 |
59 |
|
36 |
Jan 28, 1900 |
3 |
42.333 |
14 |
|
37 |
Jan 22, 1889 |
3 |
42.067 |
3 |
|
38 |
Jan 9, 1930 |
3 |
41.867 |
36 |
|
39 |
Jan 31, 1968 |
3 |
41.700 |
54 |
|
40 |
Feb 15, 2004 |
3 |
41.667 |
71 |
|
41 |
Feb 19, 1914 |
3 |
41.633 |
29 |
|
42 |
Nov 30, 1922 |
3 |
41.467 |
34 |
|
43 |
Jan 1, 1905 |
3 |
41.300 |
17 |
|
44 |
Nov 26, 1894 |
3 |
41.200 |
6 |
|
45 |
Nov 23, 1888 |
3 |
41.067 |
1 |
|
46 |
Jan 3, 1991 |
3 |
40.867 |
61 |
|
47 |
Dec 24, 1920 |
3 |
40.800 |
31 |
|
48 |
Jan 6, 1999 |
3 |
40.400 |
66 |
|
49 |
Jan 19, 1901 |
3 |
40.333 |
15 |
|
50 |
Feb 18, 1892 |
3 |
40.300 |
4 |
|
51 |
Feb 10, 1930 |
3 |
40.100 |
37 |
|
52 |
Jan 2, 2012 |
3 |
40.067 |
79 |
|
53 |
Jan 16, 1960 |
3 |
40.033 |
51 |
|
54 |
Feb 17, 1916 |
3 |
39.967 |
30 |
|
55 |
Feb 4, 2000 |
3 |
39.967 |
67 |
|
56 |
Mar 2, 1893 |
3 |
39.933 |
5 |
|
57 |
Dec 26, 1941 |
3 |
39.933 |
45 |
|
58 |
Dec 9, 1906 |
3 |
39.900 |
20 |
|
59 |
Feb 8, 1970 |
3 |
39.900 |
55 |
|
60 |
Jan 6, 1910 |
3 |
39.867 |
25 |
|
61 |
Feb 4, 1991 |
3 |
39.767 |
62 |
|
62 |
Feb 21, 1910 |
3 |
39.700 |
27 |
|
63 |
Dec 17, 2002 |
3 |
39.667 |
70 |
|
64 |
Feb 5, 2007 |
3 |
39.633 |
73 |
|
65 |
Feb 12, 1921 |
3 |
39.600 |
33 |
|
66 |
Feb 17, 1910 |
3 |
39.533 |
26 |
|
67 |
Feb 1, 1903 |
3 |
39.467 |
16 |
|
68 |
Mar 8, 1989 |
3 |
39.433 |
60 |
|
69 |
Feb 25, 1907 |
3 |
39.400 |
21 |
|
70 |
Dec 7, 1908 |
3 |
39.367 |
24 |
|
71 |
Feb 17, 1971 |
3 |
39.233 |
56 |
|
72 |
Feb 24, 1898 |
3 |
39.167 |
10 |
|
73 |
Jan 31, 1951 |
3 |
39.167 |
49 |
|
74 |
Feb 20, 2001 |
3 |
39.100 |
69 |
|
75 |
Dec 7, 1950 |
3 |
39.067 |
48 |
|
76 |
Mar 4, 1930 |
3 |
39.033 |
38 |
|
77 |
Feb 25, 1935 |
3 |
38.767 |
41 |
|
78 |
Feb 26, 1998 |
3 |
38.733 |
65 |
|
79 |
Feb 6, 1967 |
3 |
38.600 |
53 |
|