ICZM with a focus on climate change rise in development countries

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1 ICZM with a focus on climate change rise in development countries Hernan Moreano: Vice-President of COASTMAN Ecuador Foundation Introduction The low Guayas River basin (LGRB), located in the Southwest of Ecuador, is the most productive area of Ecuador. It is an important area for agriculture and aquaculture, which is the leading export products, together with oil. The contribution of this region to the GDP is 20 billion US$. Farming and aquaculture provide direct and indirect jobs to 3.2 million people on a total population of 12.1 million. The inhabitants of the basin live mostly concentrated at Guayaquil (3 millions), which is Ecuador s major port and the economic capital. Besides agriculture, the area holds a mangrove ecosystem of ha and estuarine water bodies of 5100 km 2. These are associated with the Guayas River and Estero Salado estuaries, connected with the Gulf of Guayaquil through the Jambeli and El Morro channels. The climate of Ecuador s Coastal Zone is determined by the position of the Inter Tropical Convergence Zone (ITCZ), the offshore water masses distribution and climate variability events such as El Niño Southern Oscillation (ENSO). All of these are responsible for flooding on the river basin areas and for sea level rise within the estuaries. The last ENSO event of , for the period of 10 months, impacted Equatorial Pacific coast, in this occasion the damages were valued at US$ 2.6 billions in the entire coast. This is a rough estimate made by the Latin American and Caribbean Economic Commission (CEPAL, 1998). Climate Change (CC) is a risk for Ecuador coastal zones and especially for the LGRB. For this reason we study the problems generated by CC, a final review of it was made in Four Equatorial institutions carried out the study: Instituto Oceanografico de la Armada (INOCAR), in charge of sea level rise studies in estuaries, Instituto Nacional de Pesca (INP) who must focuses its work in impacts on mangrove ecosystem, biodiversity and the shrimp industry, Instituto Nacional de Meteorologia e Hidrología (INAMHI) that focuses the research on precipitation and assessment of the low basin hydrographic system and Instituto de Planificacion Urbana y Regional (IPUR) join to the Catholic University (UCSG) for social and economic impacts in the study area. 1

2 Problem definition ICZM Under an Integrated Resources Management vision, an environment study, and the related social and economic issues, as well as a vulnerability assessment study of the Low Guayas River basin affected by climate change was conducted. In this study precipitation, sea level rise and ENSO events were considered as a matter of Climate Variability (CV) and were monitored periodically. The goals of the study included To assess the possible impacts of climate change at the present and future situation of coastal resources and their consequences on economic and social matters. To identify possible attenuation measures and projects that could give way outs with such measures. To develop planning tools for Impact Assessment on long term changes of resources and their use. To contribute to establish the Ecuador Coastal Zone management institutional structure. To support Capacity building in Integrated Coastal Management. To contribute to improve Ecuador National Communications on CC. Approach 2

3 The vulnerability assessment study was carried out all these years using the seven steps as described in the Vulnerability Assessment of Coastal Areas to Sea Level Rise. Steps 1 through 4 were made by the project coordinator and the working groups of involved institutions. Additionally a series of workshops were organized to define the boundaries of the study area, the possible climate scenarios for precipitation and sea level rise, formulation of response strategies, results assessment and a long term structure proposal to manage the Low Guayas River Basin. A common methodology focused on natural and socio-economic system impact assessment, as a consequence of the physical effects of sea level rise and on the effects of response strategies was made. The vulnerability assessment began with a delineation of the study area and specifications of sea level rise, boundary conditions. Followed a study area inventory and the identification of relevant development factors related to productivity activities, capital investment and natural values were made. After completing these three initial steps, a physical change assessment and the natural system response were determined; this included morphological development of the shore line, water level and changes in salinity. Afterward, the response options were formulated, estimating their cost and effects, all this, considering scenarios that represent cases showing the cost of the response options in each economic scenario (with and without development). The vulnerability assessment ended assessing the susceptibility of changes, forced by sea level rise and related socio-economic impacts, followed by actions to develop a long term basin management plant, based on integration and participatory decision making. Results of the vulnerability assessment Guayas and Estero Salado estuaries were selected as study areas due to its sensitivity to sea level rise. Impacts of flooding already undergo on this area, could increase in the future as a result of sea level rise and changes in precipitation. The study area perimeter is 630 km and encircles an area of nearly km2 that holds ha of banana, rice and sugar cane farming fields. The zone has a population of 3.4 million people, mostly concentrated at Guayaquil, which is a city port, located at the upper branches of the Guayas River and Estero Salado estuaries where a series of islands and archipelagos are distributed nearby; most of them are covered by mangrove forest and shrimps ponds. On the southern part are located Machala and Puerto Bolivar, the main city and port, respectively. Estuarine waters are tide driven and their volume depends on ocean currents traits, mainly at the eastern Pacific, as well as on precipitation, fresh water river inputs, caused by the southward motion of the ITCZ, and by warm ocean water masses driven by surface currents or by the ENSO event. The geometry of these estuarine systems and the differences in phases with sea level make a complicated pattern of circulation, especially near the mouth area where both estuaries are connected. Through Guayas River estuary, salinity gradients are noticeable, since fresh water inflow fluctuates during the seasons. The maximum range of the salinity intrusion is as far as Guayaquil is located; but it does not penetrate further because of Daule River permanent flow, which is controlled by the Daule-Peripa Dam, in the north part. Vertical gradients are almost insignificant and 3

4 both estuaries fall in categories 1a and 1b, in the Hansen and Rattray (1996) circulation and stratification diagram. The tidal prisms for the Guayas and Estero Salado estuaries are 4.4 billions, and 1.2 billions cubic meters respectively. The flushing time for the Guayas Estuary is between 8 to 13 days and could be less in periods of high river flows associated with El Niño. In contrast, the Estero Salado upper part, located at the west of Guayaquil, does not have fresh water inflow and its flushing time is longer than this of Guayas. Going southward and close to the mouth, the water exchange with the ocean and with the other estuary increases, consequently the flushing time decreases. All three hydrographic systems are responsible for sediment transport and fresh water inflow into the study area. The economic situation The economy of Ecuador is marked by a huge external debt of US$ millions dollars, an annual budget with lack of resources to invest in productive sectors. The economy is characterized by a low foreign investment, lack of economical, legal and political systems guarantees. The economy manages high inflation and interest rates. At nowadays the country unemployment is about 10.3%. Two sectors are responsible for one third of exports incomes; they are the agriculture and shrimps farming, both of them taking place in the study area. The population has a growth rate near 2.2% per year. Climate Scenarios Several climate scenarios were established for 2010 Scenarios Basic (SLR 0) Moderated (SLR 1) Severe (SLR 2) Conditions No changes in sea level, air and ocean surface temperatures and precipitation. Sea level rise 0.3 m, with an increase of 1 C in air temperature, Sea Surface temperature (SST) anomalies less than 1 C and a 15% reduction in precipitation. Sea level rise of 1.0 m, with an increase of 2 C in air temperature. SST anomalies over 2 C and a 20% increase in precipitation. As the study area is not affected by ocean storms, hurricanes and tornados, the climate scenarios do not consider data related to these events. Outputs of most Global Climate Models (GCM) are in Celsius degrees of air temperature variation and percentage of precipitation below or above average. Unfortunately, climate in the global context and particularly on Ecuador s coastal zone is not only related to changes in the atmosphere, but also to changes in the offshore water masses driven by surface currents. These in turn are coupled to the wind driven circulation patterns on the Pacific Ocean. The proposed INAMHI scenarios were as follows (values for 2010 compared to 1998): 4

5 Scenarios Air temperature Precipitation C - 15% C - 20% C + 20% C - 15% Year: The working group of experts agreed that scenario 1 matches with the moderate scenario for the Vulnerability assessment study, assuming an increase of water transport of the Humboldt coastal current but keeping SST anomalies < 1oC, air temperatures will increase by 1 C, precipitation will be less than overage by 15% and there will be and increase of sea level of 0.3 m. Meanwhile scenario 2 matches with the severe one, assuming an offshore warm water mass which source is the Panama basin and it is driven southward by El Niño current; SST anomalies rise over 2.5oC, air temperature will increase at least by 2oC, precipitation will be above overage by 20% and sea level rise will be 1.0. Scenarios 3 and 4 are far away from reality because with a cool ocean is impossible to have a 20% increase in precipitation and with a warm ocean is impossible to expect a decrease in rainfall. Capital lost Capital lost, at risk and at change was considered for each of the impact zones for the 1998 and 2010 scenarios. Capital lost include all flooded land and coastal habitats such as mangroves, shrimp ponds, banana, rice and sugar cane plantations, beaches and urban areas of Guayaquil, Machala and Puerto Bolivar. Losses for SLR 1 are in the order of 10% to 14% of GDP, but for SLR 2, they go up to 12,5% and 18.5% for 1998 and 2010 respectively. Major loses are from mangroves and sugar cane plantations and associated industry. Mangrove will almost disappear in the SLR2 scenario, this represents a loss of over one billion US$ without considering associated biodiversity, CO2, fixation and the role of this forest in the estuarine ecosystem. Although, the response strategy cost is high, it 5

6 could be distributed through time, which allows for the investment to keep this natural system alive. Policy implications To reduce the vulnerability of the LGRB to climate change must be build dams, irrigations and bypass channels, projects of water, hydroelectric plants and drainage systems. Most of these strategies are being designed by CEDEGE and PREDESUR* (CEDEGE 2004). During the last 10 years CEDEGE had completed the following projects: Bypasses of the Bulu Bulu and Chimbo rivers, Irrigation and drainage system of the Catarama River, The transfer of water from the Daule River to the Peninsula de Santa Elena. The Daule Peripa to La Esperanza and Poza Onda project, The 210 MWatt hydroelectric plant. PREDESUR have completed: Various drainage and irrigation projects related with the Marcabeli Dam in El Oro province. The infrastructure will reduce the risk of the study area to climate change and climate variability events like El Niño. Conclusions: The vulnerability assessment showed the vulnerability of the LGRB to climate change and climate variability. The worst case scenario (SLR2) indicates that capital at risk and capital lost together will be three billion US$. (to the next 2010). The cost benefit relation is favorable to implement the measures now, but, the cost will increase substantially high if they will be implemented for The main constrain for implementing response strategies for sea level rise and precipitation changes is that the economy of Ecuador can not bear the investments. References CEDEGE (2004) General Plan for development of the LGRB INOCAR (2005) Sea level rise IPUR (2001) Socio economical Study 6