Soulh Poclfic Reglonol Envlronmenl Progromme SPREP Reports ond Studies Series no. 82 Climate Change and Sea Level Rise Issues in Guam Report on a Preliminary Mission by Usha K. Prasad and 7 551.(\' Harley L. Manner qb+ ?Ak Oropyrtght @ Foqth Paoitio Begional Dnviroancnt PrOgrtiuine, f g04 -Ebvironmont The Siruth P, scifrc Ragioial Prpgraumo outhorises the rvprodtretion of thie rnater:ial, whole or in part, in agy fonm ptrvided apprropriato aohorrlodgornent io giveu. Origin€l Text: Euglisb Published in JUV 1'994byl South Pocific Regionol Environmenl Progromme F.Q. Box 240 Aplc, Weslem Sqmoo Commerciol Prinfers Apln, Somoor P 35/9.4 -?C Frfnled wifh ffnonclol qssbtonce from lhe Uhlled iloflons Envlinnmonl Progrcrnme ( UNEF) Loyouf by Wedelin Word. SPREP. USP Catalogulng-in-Fublication Data Prasad, UshaK. Cliurate ehange and eea levsl rise is" sues in GuFrn : repott on a preliuainary mission I by Usltra K Prasad and l{arlcy L. M.anner. - Apia, Western Samoa : SPREP, 1994. Eibliography: iv" 42p, ;29ern - (SPREP reporbs and studies scrles ; na 84, IS,BN: 982-04"0106.9 t ehm'atic chsnges - Guam 2. Sealwel - Grran 3. Guam 'Enviroamentalaspects f. Man4er, Itrarley IL Soutfu PAqific Re- giural Erwinonulent Frngranure IIL Title fV. Series QC98'1.&c5rP?2 651.625'0996? ''t I South Pocific Regionol Environment Progromme Climate Change and Sea Level Rise Issues in Guam Report on a Preliminary Mission by Usha K. Prasad University of Guam Mangilao, Guam and Harley I. Manner University of Guam Mangilao, Guam Published in JUV 1994 in Apio, Weslern Somoo Acknowledgements The authors wish to acknowledge the individuals and organizations that provided data needed for preparation of this report Special thanks to Greg Ikehara of the United States Geological Sunrey for making his office and resourees available for the duraf,ion of the study. Public agencies which provided data included the Guam Bureau of Planning, Guam Employment and Development Agency, Guam Environmental Protection Agency, Guetn Historic Presewation Ofiice, and the Office of Civil Defense. In addition, Leroy Heitz of the Water and Energy Research Institute of the Western Pacific, at the University of Guam, prwided much of the rainfall data. Rosalind Hunter-Anderson and David Gillespie ofrered helpfrrl suggestions during the data gathering phase. Also, thanks to Thelma Sarmiento for preparing the Gwernment of Guam Organizational chart, and Doreen Fernandez for photocqying USGS data. Foreword The first, Intergouernmental Meeting on Climate Change and, Sea Leuel Rise for the South Poci,fi.c Region was held in Majuro, Marshall Islands, in 1989. It was organised by the South Pacifrc Commission (SPC) and South Pacific Regional Environment Programme (SPREP) to create a public awareness on the future implications of these issues t.o the governments. Subsequently, necessary actions are being undertaken to address these issues in order to develop appropriate policies' In this meeting, SPREP member governments gave the mandate to SPREP to cgordinate and act. as the clearing house on all climate change and sea level activities for the region. The Un,i.ted Nu.1ion Enuironrnent Programrle (UNEP) then provided financial assistance through SPREP (use of SPREP Climate Change Task Team Group) to undertake preparat.ory missions to Tonga, Kiribati, Tuvalu, Cook Islands, Guam, Palau, Federated States of Micronesia, Western Samoa and Tokelau to discuss the studv with the governments, and to prepare reports before undertaking in-depth studies on the impacts of climat,e change. The main task of t.his mission to Guam was to prepare a report in close consultation with the government. officials, identifying areas for in-depth study into the potential impacts of expected climate and sea level changes on the natural environment and the socio-economic structures and activities of Guam. In addition, it, identifierl suitable and available response options to avoid or mitigate the impacts of climatic changes. It is anticipated that the Guam government will have thp opportunity to closely examine these recommendations in the report, and to advise SPREP and other organisa tion s accordin gly. (+&--"---I \l \J ---- Vili A. Fuawn Director Contents Acknowledgements..... Foreword l. Introduction.............. l.l Background I 1.2 Mission Brief.......... 1 1.3 Period of Study I 2. Guam - The Environmental Setting .. 2 2.1 Island Geography 2 2.2 Geology and Physiography....... 2 2.3 Climate...... 5 2.4 Flora and Fauna....... l0 2.5 Soi1s........... .. 12 2.6 Water Resources Lz 2.1 Land Use... l3 2.8 Cultural or Traditional Sites...... 14 2.9 Socioeconomic Setting l5 2. f0 Current Environmental Prob1ems................. 20 Global Climate Change.... .. 23 3.1 Previous Studies 23 3.2 Projections of Global Climate Change...... 23 3.3 Impact of Climate Change in the Pacific........ 24 3.4 Sea Level Rise in the Pacifrc 24 3.5 The Likely lmpacts of Climate Change and Sea Level Rise on Guam ... 25 4. Future Environmental Planning in Guam 28 6. Recotntnendations. A. Environmental Change and Response Unit........... 30 B. Fresh Water supply....... 3t C. Remote Sensing and Satellite Data........ 3l Bibliography............. .. 33 Annex Government Agencies and Research Units consulted during the study 36 tv' 1. lntroduction This included the identification of response options which may be suitable and 1.1 Background available to avoid or mitigate the etpected negative impact of climatic changes. As a result of previous studies carried out 2. Specifically, the mission is to prepare a through the support of UNEP to the South report containing: Pacific Regional Environmental Programme (SPREP) Regional Seas programme in the a. a general ovewiew of the climatological, Pacific, a number of island States are thought oceanogtaphic, geological, biglogical and to be under immediate threat of major socio-economic factors which may be environmental change, should green-house- relevant to, or a-ffected by, the potential forced climatic warming and consequent sea irnpacts of expected climatic changes; level rise occur. b. a preliminary identification of the most The problems identified have been set out in vulnerable components and sites of the both summary and detail in the reports of the natural environment, as well as the socio' Association of South Pacific Environmental economic structures and activities that Institutions (ASPEI) Regional Task Team would be critically affected by expected climatic changes; @ernetta and Hughes 1989). In these reports Guam has been identified as one of the Pacific c. an\ onewiew of current environmental Island nations most vulnerable to any sea level management problems in the country and rise which would result from climatic warming. an assessment of how such problems may It is apparent however, that climatic warming be exacerbated by climatic changes; and consequent sea level rise is simply one, d. a detailed proposal for a joint program of and in many cases not the most urgent, of a assistance to the host country, or an in' number of environmental problems facing depth evaluation of potential impacts of small island nations . Plans to deal with these expected climatic changes on the natural climatic change problems c€rn be most environment and the socio-economic appropriately considered along with other structures and activities of the country. environmental planning needs. The proposal should identify policy or The remainder of this report follows the format management options suitable to avoid or used by Sullivan and Gibson (1991), in their mitigate the impact of climatic changes, report on climatc change and potential sea together with the workplan, timetable, in'depth level rise for the island of Kiribati. financial requirements of the evaluation and the possible institutional arran gements required. 1.2 Mission Brief 1.3 Period of Study The Terms of Reference for this mission were established by UNEP and SPREP, and closely in follow the 1991 mission to Kiribati (Sullivan The study took place over seven days the and Gibson l99t). November 1991. Combined with site visits, freldwork involved meeting with, and obtaining l. The main purpose of the mission is to data from, the appropriate government prepare, in close consultation with national agencies and research facilities on island. A counterparts, an in-depth study of the Iist of the public and private agencies and potential impact of expected clirnatic facilities consulted during the data gathering changes (prirnarily sea level and phase are listed in the Annex. temperature rise) on the natural environment and the socio-economic structure and activities of the host country. 2. Guam - The Environmental Setting In turn these provinces have been subdivided 2.1 lsland Geography into seven physiographic units: a) the dissected Alifan Limestone cap of southern Guam which consists of high Guam is a small (541 square km,) tropical knobs, sharp elongated hills, scarps and island located in the Western Pacific. It is the irregular depressions ; southernmost of the Marianas islands and lies approximately 13oN latitude and 14408 b) mountain land in southwestern Guam longitude (see Fig. la and b). Guam's location, consisting of steep and dissected slopes as well as its political recognition as a U.S. formed on the Alutom and Umatac territory, make it a major port of entry for volcanics; countries of the Asian region. c) dissected and gently sloping foothills in southeastern Guam developed on the Alutom formation, the Mahlac shale, the 2.2 Geology and Physiography Bolanos pyroclastic, and the Dandan flow; d) hilly and rolling land./dissected limestone Guam is classified as a high island with an plateau developed on the Agana axial trend northeast to southwest. It has 12 argillaceous member of the Mariana small islands located on its fringing and barricr limestone of the central mountains and reefs. The island is located on the eastern edge southeastern Guam; of the Philippine Plate and northwest of the plateau Marianas Trench (see Fig. 2) where subduction e) the flat of northern Guam and the of the Pacific Plate and other plate movements Orote Peninsula capped by the Mariana result in a high number of minor earthquakes limestone; and tremors.