Eqecat has increased its market loss estimate for the Japanese earthquake and tsunami from a range of $US12-25 billion ($11.2-$23.4 billion) to a new range of $US22-39 billion ($20.6-$36.5 billion).

This represents an 83% rise to its initial bottom-end estimate, and a 56% rise to its previous top-end forecast.

The French risk modeller says a reassessment of damage caused by the onshore water depth – which it says was initially reported to be 8 metres but has been found to be in excess of 25 metres – along with insights into damage caused by liquefaction, landslides, widespread disruption of electricity and transport and loss amplification caused by the disruption at the nuclear plant in Fukushima, led to the updated loss estimate.

It says losses to property insurers are now estimated at $US15-25 billion ($14.1-$23.4 billion), with losses to marine, vehicle, life, and personal accident insurers making up the difference.

But it does not include potential losses from contingent business interruption, which is expected to emerge as a major long-tail loss from the disaster.

Rival risk modeller RMS has not updated its initial estimate of a total insured property loss of $US18-26 billion ($17-$24.5 billion), and a total insurance loss of $US21-34 billion ($19.8-$32 billion), including life and health insurance payouts. 

The update may cause some insurers and reinsurers, who initially base their individual loss estimates on the modellers’ estimates, to increase their expected losses.