June 28, 2010

By Bill Jaynes
The Kaselehlie Press

Pohnpei, FSM-If Internet news stories and blog postings are at all accurate, doubters seem to be convinced that a recently accepted peer reviewed study has fully and completely debunked the claims of Pacific Island Nations that many of their islands will be uninhabitable as a result of climate change caused sea level rise.

The thirteen page report encapsulates years of scientific study by Paul S. Kench of the University of Auckland in New Zealand and, Arthur P. Webb of the South Pacific Applied Geosciences Commission in Fiji. The report is entitled, "The dynamic response of reef islands to sea level rise: Evidence from multi decadal analysis of island change in the Central Pacific."

Their study concluded that 60 years of evidence proves that the shores of many atoll islands in the Pacific are broadening rather than narrowing as had been previously assumed.

"How are global warming believers going to spin this one," one responder asked in a comment on an internet blog posting based on news stories about the report. The logger didn't appear to have read the thirteen page technical report nor had that person bothered to interview the scientists who wrote it.

According to Dr. Webb, who was one of the two authors of the report, the only "spin" so far has been from "less than honest reports (that) are indicating that islands are 'growing not sinking,'" he wrote in an email. "This is categorically wrong! Our paper says that the outer edges-i.e. the shore-lines have, over the last 50 years or so, responded to sea-level rise (of about 120mm over that time) and in many cases the area of islands has increased-not decreased as so commonly thought."

Of course "area" only takes into account two dimensions. It doesn't include the third dimension of height.

"The critical point here," wrote Dr. Webb, "is that the land area within (the atoll is-lands) is not building vertically and thus, even if the shores are accreting (building) this will ultimately not prevent the greater land area from becoming submerged as sea level rises."

"The overall vulnerability of the atoll communities has not changed, the land is extremely low lying and sea level rates are increasing," he wrote.

Dr. Kench responded to our email from the Maldives where he and Dr. Webb were at press time, attending a meeting. Though Dr. Kench didn't specifically answer our questions regarding the fuller context of his reported quotes, he did say, "The results suggest that Pacific Island communities will face major environmental challenges over the coming century. Our work has begun to identify the way islands will change. The challenge for island communities is how they can adapt to the changes expected over the coming years."

While Dr. Kench's email response was short and poignant, Dr. Webb had much more to say. His response was equally poignant, "The positive shoreline response is encouraging, however, given sea level rise rates are increasing and other climate change stressors such as bleaching and acidification are less likely to have been a major issue 50 years ago, this resilience may not last - we just don't know and there's so little re-search in these environments that we have very limited information to guide us with regards to what future response may be.

"What is for sure," Dr. Webb continued, "is that the island's natural sedimentary systems will not just sit and be unresponsive. This study shows that they are responsive and as my colleague Paul Kench has noted 'It has long been thought that as the sea level goes up, islands will sit there.' (The reported quote by Dr. Kench included the words, 'and drown. But they won't.') The islands will respond but we must be very careful to point out that 'response' does not necessarily mean that the islands will be maintained in the form we recognize today, that is, we do not know how long an island with soils for agriculture, complex vegetation, good fresh groundwater reserves, etc. can be maintained. Indeed, given what we understand of increasing rates of sea level rise we may be talking about relatively in-hospitable gravel banks as the 'response' to the next 100 years of sea level rise. The point is we do not know at this time, and guessing does us all no favors - we need sustained, good quality research to bring improved answers to atoll communities who deserve to have the best facts possible."

On the question of vertical growth measurement of the islands the two scientists studied, Dr. Webb said, "This study did not measure vertical change nor does it suggest that whole island vertical growth has occurred. Whilst I was compiling this present research on historic shoreline response I found that the results fit my field observations well, in that many atoll shorelines in rural areas appeared to be 'healthy' or functional, that is, they continue to build and provide protection to the land behind. What concerns me deeply however is the very limited evidence I have seen of any vertical building in these central Pacific atoll islands.

"It is important to note (that) I have not at this time seen evidence which suggests widespread deposition of sand or gravel which could build the entire island vertically. I have seen isolated cases in the immediate vicinity of the beach system but not of widespread deposition over the larger land surface of the islands. Given the importance of this question, it again deserves appropriate and dedicated research. Until we see evidence which suggests otherwise, we assume island wide vertical building is not occurring, so even if shorelines remain resilient for the immediate future it would seem the greater land mass of the islands will remain very low lying (presently often less than 1m above the high tide mark) and ultimately this land will become subject to more and more frequent flooding.

"This phenomenon can be seen in Fongafale the main settlement on Funafuti, Tuvalu. Here the shoreline berm (highest part of the beach) is well above sea level, however the interior of the island is very low lying and this area floods with seawater every high spring tide. It follows that as sea levels continue to increase this flooding will obviously become more frequent and deeper, gradually rendering more and more land useless."

As to what should be done next, Dr. Webb said, "Until a few weeks ago a great many people thought that all atoll shores were uniformly erosive and this has been rather unhelpful for those who work in the field of shoreline processes. The research presented in our paper changes our understanding of this aspect of climate change impacts in these pacific island atolls. It does not suggest that these environments are not profoundly challenged by the myriad of other climate change impacts, but it does bring new important information on shoreline processes. This evidence of shoreline resilience is welcome news for those who at this time are still dependant on functional shorelines for protection.

"It is particularly important for those involved in climate change adaptation projects in the shoreline zone. Understanding that shores can still be naturally resilient changes the way we approach coastal adaptation and will assist us to make better decisions about adaptation in the coastal zone. It also means that addressing existing poor management practices in shoreline zones is an excellent 'no regrets' approach to climate change adaptation. In other words, we can view shorelines in the same way we are now managing tropical coral reef areas, by removing stress on the reef system through improved catchment management, reduced fishing pressure, etc. we hope to bolster the natural resilience of the reef system to climate change stress. Likewise, if we maintain shoreline processes and remove stress such as beach mining, inappropriate engineering etc. we can reasonably hope to bolster the natural resilience of the shoreline to climate change stress."

Dr. Kench read all of his colleague's quotes before our newspaper went to press. Apparently the two scientists are in agreement. "Well done," he exclaimed!

Some skeptical bloggers say that Pacific Island Nations have been capitalizing on the climate change phenomenon of sea level rise in order to mobilize massive amounts of financial aid but that as a result of Kench and Webb's new report, all of that funding should stop.

"I have heard over and over again also that the developed countries have 'pledged' billions of dollars for climate change 'mitigation' and 'adaptation' works but we have seen little of this yet," wrote Marion Henry, Acting Secretary for the Department of Re-sources and Development for the Federated States of Micronesia.

Henry said that he has told many of his international colleagues, "No amount of funding is going to raise my atoll island above sea level after sinking due to sea level rise."

"We should be celebrating the fact that the Pacific Islands are producing world class science and take very seriously the need for greater understanding as we face climate change stress - wouldn't that have been a nice positive spin," Dr. Webb asked?

"How are global warming believers going to spin this one?" Perhaps accurately reported authoritative sources will do.