Prolonged warm and dry spells are reducing water availability for many of Vanuatu’s 250,000-plus population. Rainfall when it arrives is becoming more intense, cutting output of the island cabbage, a staple for many residents, Ms Laban said.

“Human food security is the biggest challenge for us,” Ms Laban said, ahead a speaking tour that will take in Melbourne (August 5), Hobart (August 7), Sydney (August 8) and Brisbane (August 14).

The Gillard government granted Vanuatu’s climate change adaptation efforts $2 million over three years, as part of a $599 million “Fast Start Finance” plan agreed with the United Nations for the 2010-2013 period. The scheme included $134 million for the Pacific but the Abbott government ended support in its May budget and existing funds run out in December, Oxfam said.

Oxfam, CARE and other international agencies have been encouraging farmers to grow crops such as capsicum, beans and tomatoes which are less susceptible than island cabbage to rotting after heavy rains.

Market gardens and coconut plantations - which help provide Vanuatu residents with income for school fees and other costs - are being lost to rising seas and storm surges.  “It’s a struggle to survive as the storms reduce the size of plantations,” Ms Laban said.

Some communities are also having to tackle the unpleasant task of exhuming and relocating graves where coastal erosion is undermining cemeteries, Ms Laban said.

Bureau's view

Australia's Bureau of Meteorology issued a report on Pacific climate earlier this year, including a chapter on Vanuatu.

The bureau noted maximum and minimum air temperatures had risen over the 1948-2011 period as measured at the Bauerfield Airport near the capital, Port Vila.

Rainfall records indicate no significant trends at Bauerfield and Aneityum, the country's southern-most island, the report said, adding that "the effect of climate change on average rainfall may not be obvious in the short or medium term due to natural variability".

The risk of coral bleaching will increase as the ocean warms, with the long-term viability of reef ecosystems threatend if bleaching events occur more often than once in every five years, the bureau said.

Ocean acidification will also continue, with impacts on the health of marine ecosystems. Sea levels are likely to be 8-19 centimetres higher than the 1986-2005 average by 2030, according to the bureau's report.

Australia has contributed $32 million to the Pacific-Australia Climate Change Science and Adaptation Planning (PACCSAP) program, which will conclude during the current financial year as activities are completed, the Department of the Environment said.

Aid ends

“Pacific nations have consistently identified climate change as the biggest threat to their prosperity and development, a statement again made clearly at the Pacific Islands Forum last week," said Simon Bradshaw, Oxfam Australia’s climate change policy advisor. “So it's disappointing to see the federal government pulling funds from this important work to tackle climate change in the Pacific.”

A spokeswoman for the Department of Foreign Affairs and Trade said the Oxfam-related grants were intended to run until the end of 2014.

"The project was always intended to be completed within this time period and has not been cut," the spokeswoman said.

Ms Laban, from Nguna Island, not far from Port Vila, said past support from the Australian government had “really helped the resilience of our community”.

She added, though, that the threat from climate change looks likely to worsen as global emissions of greenhouse gases continue to rise.

Over the past 10-20 years, residents are finding themselves having to travel further to find water. “This is happening more and more,” Ms Laban said. “It makes us worry about the future.”

Fairfax Media sought comment from the Department of Foreign Affairs.

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