Iceland's Met Office has upgraded the threat level posed by a potential massive volcanic eruption. There have been thousands of earthquakes near Bardarbunga, a huge volcano in Iceland, and while so far it has not erupted, there remains a very real risk that it will start spewing ash into the atmosphere, sparking a flight delay crisis.
Over the weekend there was an earthquake of M4 magnitude, the strongest in the region for almost 20 years, sparking talk of an eruption. The Met Office in Iceland said there were "strong indications of ongoing magma movement", raising the aviation warning to orange, the second highest level of threat.
It has been four years since the last Icelandic volcanic eruption (Eyjafjallajokull) closed most of Europe's airspace for around six days, affecting more than ten million travellers, at a cost to the industry of over £1 billion. Now fears are growing of a second.
If these fears are realised, and your travel plans are affected, it's worth getting an understanding of your rights.
If you are travelling with a tour operator, and are yet to travel, you will either be offered an alternative destination or date - or they will cancel the holiday and offer a full refund.
If you are travelling with a tour operator and you are already overseas, they will be responsible for arranging additional accommodation and flights home as soon as possible.
If you have booked everything separately, your airline will be responsible for either switching to an alternative destination or date - or cancel and offer a refund of the flights. It will be up to you in these instances to try to arrange a refund for your accommodation and any other costs.
If you are travelling independently you should also check your travel insurance policy. Caroline Lloyd, Gocompare.com's travel insurance spokesperson, said: "Many 'Acts of God' or natural disasters are typically not covered by insurance providers - most policies will have an area detailing the exclusion. As such, customers should carefully read all their policy documents to see if instances of travel disruption are excluded."
Some insurers have already announced that in the event of an eruption they will cover all passengers who have bought their policies. LV= was one of the first insurers to make this commitment last week. It said that in the event of an eruption that causes delays of more than 24 hours, LV= premier travel insurance customers will be covered for the cancellation of their holiday, or will receive up to £1,000 towards other travel and accommodation costs so they can still get to their destination. For LV= premier travel insurance customers who are already abroad and can't get home, LV= will offer cover for the cost of additional travel or accommodation costs up to £1,000.
"If you've travelled independently, check with your insurer what cover you're entitled to," Lloyd says, adding that after the 2010 ash cloud, a number of insurers added a travel disruption element of cover, typically available as an upgrade, or in some instances as a stand-alone policy. Holidaysafe.co.uk, for example, offers Platinum cover which covers you for ash cloud cancellation, or standard cover which only insures you if you discover your flight is being delayed by volcanic activity after you have checked your luggage in.
"If you bought your policy before you knew about the ash cloud," she says, "it's likely you'll have some level of cover. However, this can vary between policies and not all insurers have amended their policies to cover volcanic ash, so it's well worth calling your insurer and finding out before you go."
And if you booked to travel to the affected area since the latest announcement, it's important to check with your insurer that you are covered, as they may take the view that you would have been aware that volcanic activity was likely to cause travel disruption.
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