Announcing the 2013 CRESTA Zones
CRESTA (Catastrophe Risk Evaluation and Standardising Target Accumulations) helps brokers and reinsurers manage natural hazard risk, based on the zoning system established by the world’s leading reinsurers. While peril-independent, CRESTA has established a uniform and global system to transfer, electronically, aggregated exposure data for accumulation, risk control and modelling among insurers and reinsurers.
Major Changes
After an extended period of industry engagement and development, the CRESTA Secretariat (currently with the Munich Reinsurance Company) has released the 2013 CRESTA zones specification. The major changes include:
- The number of countries covered has increased from 86 to 138
- The concept of Sub-Zone has been removed
- The concept of “high resolution” and “low resolution” zones has been introduced. This naming convention is a little misleading as it has no bearing on accuracy or map scale, but reflects the granularity of zones. e.g. a single low resolution zones may contain several high resolution zones. High resolution zones are intended for data exchange and modelling natural hazards whereas low resolution zones are for accumulation management and visualisation purposes.
The net effect of these changes is an increase from approximately 43,000 to over 250,000 zones. The new zones are mostly based on post/zip code regions and administrative boundaries.
Challenges
The new standard is not without challenges, including:
- The political model used is not up-to-date and many small countries are managed as part of their larger neighbours. Further, the country bundling seems to have been implemented without regard for political sensitivities. e.g. The British Overseas Territory of Gibraltar is handled as part of Spain. Some careful consideration should be taken as the standard may not be compliant with an the political policy of the organisation or its home nation.
- Some of the post/zip code boundaries incorporated into the standard were not current as of 2013
- The use of full post/zip codes results is a large number of zones which increases exposure to change. Postal authorities change post/zip codes all the time but the CRESTA standard is effectively frozen. For example, the US Postal Service has issued over 240 zip code changes in 2014, but none of these will be reflected in the CRESTA standard. Sadly, the gap between the latest post/zip code data and the standard is widening daily and it is not safe to assume that a building with post/zip code 12345 will be in CRESTA zone XXX_12345.
The large number of CRESTA zones does mean that management without Information Technology is difficult. A digital implementation of the standard for Geographic Information Systems (GIS) does, however, have the advantage of being spatially linked to hazard data as well as human dimensions such as population and demographics.
Global CRESTA Plus
Europa Technologies (UK), working in cooperation with MB International (Germany), has released an independent GIS implementation of the standard called Global CRESTA Plus. Europa Technologies was part of the team who brought the standard into the digital mapping era and has maintained a CRESTA zone mapping implementation longer than any other vendor. Using their experience as a supplier to Fortune Global 500 companies, including Google (Google Earth / Google Maps), Global CRESTA Plus is the only known product to implement the standard in the context of a well-maintained, up-to-date, political map.
