What is an ‘Indian Summer’?

“”The air is perfectly quiescent and all is stillness, as if Nature, after her exertions during the summer, were now at rest.” – John Bradbury, 1817.

autumWe often hear the term ‘Indian Summer’ brandished around when we experience fine, warm conditions at this time of year, but what exactly is an Indian Summer and how often do we experience them here in Ireland?

The term originated in North America, possibly around the New England region, although it remains unknown as when it first came to into use, or by whom. Continue reading

Why The Sky Is Blue…And Red

Crepuscular rays from the setting sun at the Phoenix park, Dublin. These rays are due to Mie Scattering and appear white. Image: Author
Crepuscular rays from the setting sun at the Phoenix park, Dublin. These rays are due to Mie Scattering and appear white. Image: Author

Ok, a lot of the time the sky is grey in Ireland, but we do get our fair share of blue skies and spectacular dawns and sunsets. But why does the sky have a blue/orange/red colour? Why not white, or black? The truth is it contains all of these colours, it just depends on where you view it from.

Before explaining the reasons why, however, let’s take look at what light actually is. Light is electromagnetic radiation of wavelengths that are visible to our eyes. Electromagnetic radiation occurs when electrons in an atom receive enough energy to cause them to vibrate billions of times a second, each time emitting photons (parcels of energy) of a particular energy and hence wavelength. This wavelength depends on the atom (i.e. substance) and on which electrons within that atom are doing the vibrating.

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Contrails v Chemtrails: The Science That Debunks The Conspiracy

Contrail over Kildare. Image Author
Contrail over Kildare. Image: Author

There are those who claim that the trails we see behind aircraft high in the sky are not the normal condensation of water vapour from the hot exhaust gases but are in fact chemicals that are being deliberately sprayed upon us by government agencies for some dark and sinister reasons. When asked to prove their claims, however, their response is invariably either just a video or blog of someone else making the same unsubstantiated claim, or a simple “Well why don’t you prove that they’re NOT chemtrails!”. Proof has been given time and time again but ok, here it is one more time, using only sound scientific methods and no political mumbo-jumbo.

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Autumnal Chill In The Air

This morning has seen the first real chill in the air as a cold polar airmass and longer nights set it.

According to this morning’s 0600 UTC synop reports the coldest station last night was Gurteen in Co. Tipperary, where clear skies allowed the air temperature to fall to 1.1 C and the grass temperature to a frosty -2 C. Second coldest was Casement, Co. Dublin, on 2.4 C air and -1 C grass, with nearby Dublin Airport on 3.5 C air and +1 C grass. Finner, Co. Donegal, also reported a grass min of -2 C, though the air temperature only fell to +3.7 C.

Mt. Dillon in Co. Roscommon was reporting 2 C air temperature on met.ie at 7 am but as no synops are issued for that station or the other recently-added automatic stations we will have to wait until tomorrow for the exact figures for all stations.

It wasn’t widespread cold, however, as the south was enjoying temperatures above a “balmy” 9 C (Sherkin Island 9.6 C). Along the coast the sea, which is at its warmest now, keeps the temperature much higher than inland, where clear skies allow the land to lose longwave radiation to space, causing the low ground-temperatures and hence chilly air-temperatures.

Turbulence Injures 12 Off Coast Of Brazil

If you ever needed proof of why it’s a good idea to keep your seat-belt attached when seated on a plane then this is it. Twelve people aboard a TAM A330 flight from Madrid to São Paulo, Brazil, were injured when the plane encountered severe turbulence off the northeast coast of Brazil early this morning. Any person or item not tied down was thrown against the ceiling as the plane suddenly descended. The crew diverted to nearby Fortaleza where the twelve people were taken to hospital. 
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‘Best Summer since 2006’

With sunshine totals finishing above average over most of the country and rainfall totals coming in below, Summer 2013 was the best since 2006 according to Met Éireann in their just published summary of the season.

IMG_2348At 16.3 Deg. C, Shannon Airport recorded the highest mean temperature of the season  with the absolute highest maxima of 31.0 Deg being recorded at Dooks in Co. Kerry on July 19th.  The lowest reported temperature of the Summer occurred at Mount Dillon, Co. Roscommon on June 5th when 2.8 Deg. C was recorded here. Continue reading

2013 Hurricane season off to a slow start

The 2013 North Atlantic tropical cyclone count stands at 6/0/0 meaning 6 named tropical storms so far, and no hurricanes or obviously major hurricanes. This is a similar start to 2011 which stood at 8/0/0 until Irene formed and quickly became a hurricane near Haiti on 22 August. Going back a bit further, this is the longest wait for a hurricane since 2002 when the count was also 6/0/0 at the end of August and Gustav (not the one in 2008 that hit Louisiana, but a visitor to Nova Scotia, Canada) became a hurricane on 11 September. Continue reading