Marine Atlas: Maximizing Benefits for Vanuatu

STORMY TIMES: CYCLONES Tropical cyclones pose direct threats to Vanuatu, its people and its marine life. Marine and coastal habitats including mangroves, seagrasses and coral reefs play an important role in offering effective protection and therefore need to be sustainably managed and conserved.

While being the strongest, the category 5 Cy- clone Pam is but one track on the map showing all category 1 to 5 cyclones that occurred in the period from 1980 to 2016. Pam formed east of the Solomon Islands on 6 March 2015 and tracked slowly south, most heavily impacting the southern islands of Vanuatu before beginning to weaken on 14 March. Cyclones are monitored by the Vanuatu Meteorol- ogy and Geohazards Department and categorized according to the Australian and South Pacific Cat- egory System from category 1 (90 km/h gusts) to category 5 (280 km/h gusts). The cyclone season is considered to run from the beginning of Novem- ber to the end of April, but destructive cyclones can occur outside this period. The formation of cyclones in the region is strongly influenced by the El Niño–Southern Oscillation (ENSO; see also chapters “Go with the flow” and “Hotter and higher”). During El Niño years, cyclones are more likely to form between 6°S and 18°S and 170°E and 170°W. During La Niña years, slightly fewer tropical cyclones form and the origin moves to the south (Chand and Walsh, 2009). On average, Vanuatu receives 2–3 cyclones per season, with around 3–5 cyclones per decade causing severe damage (VMGD, 2017). In the past decade, there has been increasing at- tention on the relationship between climate change and the frequency and intensity of cyclones in the region. Diamond et al. (2013) found a statistically

A trail of destruction

Grounded yachts were not the only wreck- age Cyclone Pam left in its wake. Residents around the country, particularly those in the southern islands, were shocked to witness the toll that Pam had taken on the coral reefs. Over large areas, the force of the waves had dislodged large coral formations and moved heavy boulders great distances, greatly changing the structure of the eco- system (see also chapter “Reefs at risk”). Cyclone Pam, gusting at 280 km/h, killed at least 15 people, left another 75,000 home- less and destroyed 90 per cent of food crops. The financial toll amounted to approx- imately AUD $590 million—more than half of Vanuatu’s gross domestic product (GDP). significant increase in the number and intensity of cyclones in the period 1991–2010 compared with the period 1970–1990. Rising SSTs are fuelling cyclones (see also chapters “Hotter and higher”) that are resulting in increasing damage, including to Vanuatu’s valuable coastal habitats. At the same time, conserving habitats such as cor- al reefs and mangroves offers a very effective form of protection against storms. In this way, Vanuatu can strengthen its defences against cyclones.

Graveyard of the yachts after Cyclone Pam at the old BP wharf in Port Vila.

MAXIMIZING BENEFITS FOR VANUATU

CLIMATE CHANGE THREATS

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