Xmas/New Year transport and travel trouble

There are usually more disasters and major foul-ups over this period, but this year has been unusually bad:

Glasgow bin lorry crash: Tributes to the victims

King's Cross reopens after day of travel chaos

AirAsia QZ8501: Indonesia plane 'at bottom of sea'

Italy ferry fire: Evacuation hampered by winds

Virgin Atlantic VS43 lands at Gatwick Airport after undercarriage failure

Any more I've missed?

As to why this happens, I do not know. Either more people are travelling on different routes; too many staff have bunked off on holiday; the weather is worse..? None of which explains the AirAsia thing, as down there the weather is the same all year round and people pretty much ignore Xmas.