Yarren District, Nauru and Hamilton, New Zealand (PRWEB) August 26, 2010
The Environment Division of the Department of Commerce, Industry and Environment of the Republic of Nauru in collaboration with CLIMsystems Ltd. of New Zealand have generated a range of climate change and sea level rise results that will form the background for the country’s SNC (Second National Communication) reporting to the United Nations Framework Convention on Climate Change (UNFCCC).
Last week the Environment Division of the Department of Commerce, Industry and Environment sponsored the second workshop in a series that has linked Nauru with CLIMsystems, the developer and service provider, for a customized version of SimCLIM called NauruCLIM. The software has been customised for use by Nauru with a local very high resolution (5 metre) digital elevation model for the island of Nauru and climate and other data specifically designed for application in the Pacific Island nation. The island and its inhabitants are acknowledged as being on the front line in terms of effects due to climate change and, in particular, its placement in the path of the ever shifting ENSO (El Niño/La Niña-Southern Oscillation) made for an especially interesting set of analyses. The combination of rising sea levels, ocean acidification, sea surface temperature changes and exacerbated extreme events such as droughts and heavy localized rainfall events are just some of the more visible examples of global environmental change occurring across the region. Smaller, incremental changes in the underlying climate also impact on day-to-day activities such as implementing the well-known rehabilitation programme for the extensively mined island. Salt water intrusions, degradation of the fringing reef, problems of freshwater supply during extended droughts, vector borne disease outbreaks during extended periods of wet weather and flooding during extreme rainfall events have already occurred and could become more prevalent. Both can be linked to increasing temperatures and shifts in precipitation regimes that now exceed very sensitive thresholds. Under the auspices of the UNFCCC and with funding from GEF through UNDP, Nauru and all the other nations of the Pacific are required to complete their Second National Communication. This document should express the underlying risk and vulnerability of the nation to climate change and define priority areas and adaptation activities so as to reduce climate impacts.
Nauru’s Environment Division of the Department of Commerce, Industry and Environment of, contracted CLIMsystems to provide not only a customised modeling system for the island nation but also technical backstopping in implementing its application. An enduring relationship has been formed and is based on excellent communication between the full membership of the Second National Communication Team in Nauru headed by Nodel Neneiya but with representatives from Agriculture, Water, Forestry, Fisheries, Quarantine, Lands, Tourism, Energy, and other specialist areas as required to complete the assessment. The Workshop of August 2010 saw the handing over of several new tools and specific training in a range of applications. One of the most helpful developments for the Nauru team was the turning over of a high resolution NauruCLIM that included 21 general circulation models, tools for generating ensembles, running rainwater tank simulations which include the application of climate change scenarios and also the consideration of reverse osmosis technology and tanker deliveries. Also included in the turnover was a customized version of PlantGro so that the Agriculture and Rehabilitation groups can explore possible alternative crops and trees for the fragile island nation.
Using the wide array of digitised site-specific time series data at one minute, daily and monthly resolutions a range of analyses were done using the extreme event tool in NauruCLIM for direct application in Nauru’s Second National Communication. For example, through analysis in NauruCLIM we were quickly able to assess trends in precipitation for the island nation. While precipitation is well known to be variable and reflects various cyclical climate phenomena that pertain to the Pacific, the general trend is toward a wetter Nauru. However, there are years when the annual precipitation has not and, may not, exceed that which is received in a single month during a wet phase. The driest year on record for Nauru was only 278 mm in 1950 and the wettest was 4588 mm in 1930. The wettest month was in January 1932 with 866 mm. The island nation’s rainfall is very closely correlated with the ENSO phase with heavier than average annual rainfall clearly related to mild to strong La Niña events and drought related to similar magnitude El Niño events. This year while wet in the first half is trending toward being dry to very dry in the second half as the current El Niño evolves and strengthens into early next year.
Another important activity completed during this visit enabled sea level data to be analysed using NauruCLIM and other software products developed by CLIMsystems. The NauruCLIM sea level rise scenario generator is one of the more powerful climate impact assessment tools in that it considers local tidal trends and land movements, over time, in its computation of potential sea level rise scenarios. During the August workshop Nauru data from Australia’s National Tidal Centre for the past 17 years was analysed for tidal extremes and trends using tools developed by CLIMsystems. The data was then entered into Excel so that a trend line could be constructed of the tidal change and vertical land movement. The derived figure of 4.85 mm a year was then entered into the NauruCLIM sea level rise scenario generator.
By 2100 a possible sea level rise of 470 mms for Nauru was found when a high climate sensitivity was applied to a worse case story line for global greenhouse gas emissions within the global climate system. The worst case from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change for the world was 590 mms. Geographically, Nauru and the tide gauge are located in a relatively seismically stable zone of the Pacific and, is in fact, very slowly rising, which lessens the real rate of sea level rise. It is important to note that this is just one scenario of possible sea level change and the data record is modest. However, this analysis points to the possibility that sea level rise is not the most critical concern for the reefs of Nauru. On a much shorter time period, sea surface temperatures and, especially ocean acidification, will further impact on the health of vitality of the fringing reef. This has implications for the adaptation planning that Nauru must consider.
The strength behind the NauruCLIM modeling system is the inherent ability for the generator to quickly and efficiently construct alternative scenarios based on different assumptions about the future. The range of possibilities and the uncertainty that they represent forms the basis for a high quality risk and enhanced adaptation option assessment.
Nauru’s Second National Communication team will conduct stakeholder interviews during the remainder of 2010. They plan to complete their SNC document by early 2011. The document will include Nauru’s greenhouse gas inventory which is currently underway.