Oil in the arctic costs $40 or more to extract. Oil in Saudi-Arabia costs, what, $15? So at the very least there is a 50% exposure as the oil price will fall for all oil. It is not like Norway is the sole exporter. If oil price drops and there is a race to the bottom, only the cheap sources will sell. Norwegian oil is among the most expensive to produce (that is currently operated with the hope of profit).

If oil price drops too far you coild imagine gasoline and diesel generators taking over for gas :p or at least NLG taking a hit... the energy market is coupled.