By Paul Homewood
In their article about a WMO report, the Age inform us that the Bureau of Meteorology had to add extra colours to its charts during Australia’s record summer of heat.
As the map shows, the purple patch sits over South Australia. So how hot was it there last summer?
It appears, much cooler than the record summer of 2000, and not even as hot as the summer of 1938.
I wonder how they managed without a pink crayon then?
Thank you to Chryphia and Renato Rio for finding lots of information on Tungurahua, including the Instituto Geofísico Escuela Politécnica Nacional (IGEPN)’s excellent website.
Tungurahua woke nearby residents with an explosive eruption at 11:51 UTC (06:51 am local time) on Sunday 14 July 2013 (VA report ). The eruption could be heard as far away as Guayaquil . The initial eruption column reached an altitude of 5.1km. A few hours later the column was observed to have reached 8.3 km. The ash cloud drifted northwest, north and northeast of the volcano. Pyroclastic flows were produced, including one down the ravine of Achupashal on the west side of the volcano. Ash fell on towns close to the volcano.
Here is the seismogram showing the onset of the eruption:
Tungurahua (5,023m) is an andesitic-dactitic stratovolcano located in the Cordillera Real in the Andes Mountains, Ecuador. The…
View original post 245 more words
The concept of “sea level” is a curious beast because the oceans aren’t level.
This irregular “sea level” is also continuously moving.
However, after about nineteen years it is possible to calculate the Local Mean Sea Level for a given location provided everything else remains constant.
Local mean sea level (LMSL) is defined as the height of the sea with respect to a land benchmark, averaged over a period of time (such as a month or a year) long enough that fluctuations caused by waves and tides are smoothed out.
Nineteen years is preferred because the Earth, moon and sun’s relative positions repeat almost exactly in the Metonic cycle of 19 years, which is long enough to include the 18.613 year lunar nodal tidal constituent.
Unfortunately, not everything remains constant.
The Earth’s surface rises and falls vertically.
The Earth’s crust stretches and compresses horizontally.
View original post 883 more words