The ices of Greenland and Antarctica bear the fingerprints of a monster: a gigantic volcanic eruption in 539 or 540 A.D. that killed tens of thousands and helped trigger one of the worst periods of global cooling in the last 2,000 years. Now, after years of searching, a team of scientists has finally tracked down the source of the eruption.
The team’s work, published in Quaternary Science Reviews, lays out new evidence that ties the natural disaster toIlopango, a now-dormant volcanoin El Salvador. Researchers estimate that in its sixth-century eruption, Ilopango expelled the equivalent of 10.5 cubic miles of dense rock, making it one of the biggest volcanic events on Earth in the last 7,000 years. The blast was more than a hundred times bigger than the 1980 Mount St. Helens eruption and several times larger than the 1991 eruption of Mount Pinatubo. It dealt the local Maya settlements a blow that forever altered their trajector……
Dull’s team also revised their estimate of Ilopango’s size, taking into account the thickness and spread of Tierra Blanca Joven deposits. They say that Ilopango may have even dwarfed the 1815 Tambora eruption, a huge volcanic event that ushered in “a year without a summer” because of the global cooling it caused. Ilopango likely launched up to a million tons of sulfur miles into the sky, high enough for stratospheric winds to spread the aerosols worldwide and trigger global cooling.…..
The Queensland coastline from Bowen to Townsville has a more west-northwest orientation than the rest,
and even westerly in the Townsville region. The prevailing east-southeast trade winds therefore blow
more parallel to the coastline over this section producing lower rainfalls – the area being known as the
Dry Tropics. A range of hills from Cape Cleveland, northeast of Townsville runs to the south of
Townsville near Majors Creek, further protecting the Townsville region from the Trades. Therefore this
area is ideal to study for monsoonal influenced summer rains, with the monsoon flow being predominately
from the northeast to north. This region is also affected by PDO,ESNO,IOD and at the southern end of
MJO influences. And all these factors whether singly or in tandem can help to influence the rainfall
totals. As well as the coastline orientation, the lack of nearby coastal ranges largely negates rainfall
being boosted by the Trade Flow. My studies have shown these summer rainfalls may also be partly
influenced by the Solar Cycle in some instances, again whether singly or in tandem with other influences
as mentioned earlier. The attached graph shows the monsoonal summer rains, generally maximized between
November and April expressed as a percentage of the average of this 6 month period against the Solar Cycle
each year in January, back to reliable record gathering in 1872. For comparison is a similar graph for Brisbane
summer rain ( Dec to Mar ). Brisbane summer rainfall is more influenced by southern patterns then Townsville
therefore the similarities are not as well defined. One interesting parallel with the two sites is the very
long time it took to cast off the influence of the Federation Drought ( Brisbane more so than Townsville )
with the summer rainfall peaks moving generally upward roughly in line with the upwards movement of the
solar peaks from the Federation Drought period up to about 1960. The 2 graphs follow…..’
Red colour marks times when rainfall was in the lowest one percent of occurrences. The graph is novel, in that the beginning of drought is marked as well as the end.
There were just six great droughts lasting more than one year: 1902, 1911, 1940, 1946, 1965, 2018. Very long droughts persisted for forty years from 1910 to 1950, then they ceased for the next forty years. The pattern does not match a model of climate change that supposes that droughts have been getting (a) more frequent or (b) more extreme.
XMETMAN says ” There is such a black art into figuring out the relative strengths of an El Niño or La Niña event, that it’s with fear and trepidation that I say that the current 2015-16 El Niño cycle is the second strongest in the records which started in 1950″
The mean temperature for December was 9.67°C which was a remarkable +5.02°C above the 1961-1990 long-term average for the month. It was 1.58°C warmer than the last warmest December of 1934 a record that lasted for over 80 years