>> Friday, April 16, 2010
My normal morning post and discussion is below....here is Robert's write-up for today....
Hot today and cooling off through the weekend. Expect temperatures today in the Mid 80s with plenty of sunshine, clouds will begin arriving tomorrow morning with temperatures dropping into the low 70s for highs this weekend.
With recent news of the volcano in Iceland affecting travel in the UK and other Western European countries, I figured it would make a good blog post. First of all the ash and volatile material expelled from volcanoes can clog and disrupt airliner jet engines. Going on the advice of the Met Offices in the UK, officials decided to postpone most flights with limited flights out of Northern Ireland. This precaution is based on the 1982 event where a British Airways 747 flew threw an ash cloud losing all four engines descending 36,000 feet in altitude before engines could be restarted.
Besides affecting airway traffic volcanoes have an extensive history of affecting weather. The most excessive and disturbing affect is climate based. Due to stratosphere forced particulate ash as well as sulfate particulate, oxidizing reactions create sulfur dioxide aerosols which circulate the atmosphere for weeks to months depending on height level before they eventually fall back to the surface. These aerosols act as cloud nuclei for water molecules allowing for more and typically dry clouds to form. These clouds which cover more of the sky (little or no rain) create an albedo effect limiting solar insulation and therefore dropping global temperatures anywhere from a half a degree Celsius to 3 degrees globally.
Recently in 1991 we saw temperatures drop below average after the eruption of Mount Pinatubo. However, this eruption was dwarfed by the eruption of Mount Tambora in 1816. 1816, which is now know as the “year with no summer”. Global temperatures drop drastically and reports of heavy snowfalls in the northeast up to June. The Northeast recorded frost every month in the summer and heavy crop failure in the entire world. Summer crops are highly sensitive and cell walls rupture at any slight frost. It is believed that with the limited oats crop the bicycle was developed as an alternative means to horse travel.