The Impacts Of Climate Changes Environmental Sciences Essay

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Globally, Peru is considered the third most vulnerable country to climate change Brooks Adger, 2003 with current trends indicating rising temperatures, sea level rise and an increase in extreme weather events (El Niño Southern Oscillation). Climate has significant impacts on the productivity of fisheries and the coastal regions of Peru are already subject to considerable climatic variability (Bell et al., 2011). This briefing examines the effects of climate change on the artisanal fisheries of Peru and explores possible adaptations to preserve their productivity for the future.

The coastal waters of Peru support the most productive fisheries on earth, accounting for nearly 10% of the global fish catch, attributable to the nutrient rich coastal upwelling known as the Humboldt Current (Chavez et al., 2008). According to Ministry of Production sources approximately 170,000 people rely directly upon the productivity of the Humboldt for their daily income, 65,500 of these people employed in artisanal, small scale, fisheries. The artisanal fishing fleet is integral to Peru's food security, catching up to 400,000 tons of marine life per year (Arellano & Swartzman, 2009). Regardless of continued frosts, droughts and El Niño events the artisanal fisheries of Peru are considered ill prepared to confront the impacts of climate change on these rich fishing grounds (Rubio, 2007).

Impacts of climate change on Artisanal Fishing in Peru:

El Niño Southern Oscillation

Figure 1 - Graph to show influence of sea surface temperature on anchovy catch. (Barange M. 2002)The El Niño Southern Oscillation (ENSO) is a major source of concern; occurring every 3 - 7 years ENSO refers to a change in the Pacific Ocean atmospheric pressure system. In El Niño years, atmospheric pressure changes result in a weakening of trade winds allowing warm waters to migrate east across the pacific suppressing the Humboldt and consequently reducing the productivity of artisanal fisheries (FAO, 2007); figure 1 indicates the close correlation between increased sea surface temperature and reductions in anchovy catch corresponding to ENSO events. The 1997/98 El Niño year induced a 55% reduction in total fish catch compared to 1996 (Daw et al, 2009) with amplified negative impacts as a result of extreme precipitation damaging infrastructure preventing products reaching market (Alison et al, 2005). Conversely, 1997/98 ENSO conditions also triggered an increased growth rate of octopus and scallops and attracted tropical species such as mahi-mahi proving initially profitable for artisanal fishermen (Alison et al, 2005). However benefits were undermined by a lack of appropriate equipment and a fall in the market price of mahi-mahi to below US$1 (Alison et al, 2005). It is clear that ENSO has a significant influence on fish stocks yet there is uncertainty surrounding the response it may have to climate change (Latif & Keenlyside, 2009). Multi-model simulations of the projected change in amplitude and frequency of ENSO under current climate change scenarios all reveal continued interannual variability (IPCC, 2007). Merryfield's (2006) analysis of the model ensemble demonstrated an increase in ENSO amplitude in a warmer climate, however conclusions drawn specify, with the high levels of uncertainty, there is no consistent indication of possible future changes (IPCC, 2007). The unpredictability of future ENSO events and their subsequent impacts on marine ecology puts emphasis upon the need for artisanal fisheries to adapt with regard to location and type of catch, in response to future variations in climate.

Sea Level Rise

Projections for coastal Peru predict a sea level rise between 0.60 and 0.81 meters by 2100 (IRG, 2011), proving detrimental for 47% of the coastal population (approximately 61,000 people) of which the majority are artisanal fishers and their kin (Met office, 2011). The consequent flooding and erosion threatens the infrastructure, homes and the health of fisheries and marine ecosystems, with damages estimated to cost US$168.3 million (Magrin et al, 2007). Additionally the displacement of population and salinisation of coastal areas threatening the fresh water supply may have severe socio-economic consequences for the artisanal fishing communities (Magrin et al, 2007).

Sea Surface Temperature:

Sea surface temperature is projected to increase by up to 2.6°C over the next century (IPCC 2007), negatively affecting the health of marine life and the productivity of fisheries (Daw et al, 2009). Warm water suppresses the nutrient rich upwelling which pelagic food chains rely upon, with the potential of driving these ecosystems towards the open ocean upwelling zones (Magrin et al, 2007). With regard to artisanal fisheries this represents reduced fish catch coupled with increased expenditure due to transportation costs (Magrin et al, 2007); under the scenario of a sea surface temperature increase of 1.2°C equivalent to ENSO of 1983 reductions of 60% in fishing effort can be expected (Alison et al, 2005). In spite of this, warmer water encourages the migration of sub tropical fish and expands the distribution zone of some species bringing new economic opportunities to artisanal fishermen (Daw et al, 2009). Applying the same scenario an influx of panaeid shrimp, mahi-mahi, tuna and diamond shark may appear beneficial however due to limited resources artisanal fishermen will be slow to adapt to new techniques and equipment (Alison et al, 2005).

Ocean Acidification

Increasing concentrations of atmospheric CO2 cause the ocean to become more acidic, evident by a current average decrease in pH of 0.1 compared to 1750 levels (IPCC, 2007). Projections characterized by SRES scenarios forecast further reductions of ocean surface ph between 0.14 and 0.35 affecting marine ecosystems (IPCC, 2007). When CO2 dissolves in sea water weak carbonic acid is formed negatively impacting on the availability of dissolved carbonate vital to marine calcifying organisms impacting on marine food chains affecting fish stocks (Bell et al, 2011). Further research is needed to quantify whether future levels of CO2 will be directly detrimental to marine fisheries possibly inducing adult fish mortality or alterations in reproductive success (The Royal Society, 2005).

Future Adaptation:

An ecosystem subject to overfishing is more likely to collapse when stressed by the effects of climate change (Adaptation Fund, 2012). Thus, the promotion of marine protected areas and sustainable fishing measures will help maintain fish stocks building resilience to the impacts discussed earlier (Adaptation Fund, 2012). Although a minority of fishermen already adapt with regard to location and type of catch in response to climate variability, there are doubts that the current level of adaptive capacity is sufficient to respond to the expected increased vulnerability (FAO, 2007). The provision of appropriate gear corresponding to changes in abundant species will allow for the informal adaptation of artisanal fishers (Daw et al, 2009). In conjunction, it must be made clear to policy makers the importance of improved climatic surveillance, with predictions made available to fishermen concerning changes in ocean currents and their consequent impacts on fish stock (Adaptation Fund, 2012). Providing access to higher value markets will help to offset any losses experienced by reduced fishery productivity and yield (Daw et al, 2009). Finally, investment must be considered into further research to quantify localised impacts of climate change on Peru's coastal regions, with the intention of indentifying areas in need of coastal defences to protect communities from the direct impacts of climate change (Adaptation Fund, 2012).

Annotated Reference List:

Adaptation Fund Board, 2012, Proposal for Peru, Project and Programme Review Committee, Bonn, Germany

This very recent proposal for Peru regarding adaption to climate change was very useful, providing information on the importance of artisanal fishing and exploring many adaptation options for the future.

Allison, E.H., Adger W.N., Badjeck M.C., Brown, K., Conway, D., Dulvy, N.K., Halls, A., Perry, A. and Reynolds J.D., 2005, Effects of climate change on the sustainability of capture and enhancement fisheries important to the poor: analysis of the vulnerability and adaptability of fisherfolk living in poverty, Fisheries Management Science Programme Project No. R4778J. MRAG, London.

This technical report gave great detail of the effects of climate change on fisheries and the vulnerability and adaptability of small scale fishing operations. The table on page 53 linked effects and impacts and was very useful when applying the effects to artisanal fishing in Peru. This was the main source for most documents I read.

Barange, M., 2002, Influence of climate variability and change on the structure, dynamics and exploitation of marine ecosystems, In Global Environmental Change (eds R.E. Hester & R.M. Harrison), pp. 57-82. The Royal Society of Chemistry, Cambridge.

Figure 1 was taken from this source along with information on the effects of ENSO and their impact on fishing.

Daw, T., Adger, W.N., Brown, K.,Badjeck, M.C., 2009, Climate change and capture fisheries: potential impacts, adaptation and mitigation. In K. Cochrane, C. De Young, D. Soto and T. Bahri (eds). Climate change implications for fisheries and aquaculture: overview of current scientific knowledge. FAO Fisheries and Aquaculture Technical Paper. No. 530. Rome, FAO. pp.107-150

This research document gave information on the effects of ENSO and increasing sea surface temperature on fishing. Additionally it explained the adaptive capacity of artisanal fishing currently and suggested ways to offset any future losses in fish yeild

FAO. 2007. Building adaptive capacity to climate change. Policies to sustain livelihoods and fisheries. New Directions in Fisheries - A Series of Policy Briefs on Development Issues. No. 08. Rome. 16 pp. Also available from:

This document from Food and Agriculture organisation of UN gave relevant information on how NGO's can aid fishing communities and also contained numerous summarising tables of effects and adaptations useful throughout my brief.

IPCC, 2007, Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, UK, 581-615.

IPCC reports quantified the effects of climate change with statistics and also provided information of models and scenarios predicting future effects of climate change.

IRG, 2011, Peru climate change vulnerability and adaptation desktop study, Written for USAID under the climate change resilient development task order, International resource group, Washington

This gave a good overview of how to focus my report for an aid organisation and provided statistics relating to projected sea level rise.

Magrin, G., C. Gay García, D. Cruz Choque, J.C. Giménez, A.R. Moreno, G.J. Nagy, C. Nobre and A. Villamizar, 2007, Latin America. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds.,

Cambridge University Press, Cambridge, UK, 581-615.

This contribution to IPCC report gave impacts of sea level rise for Peru, supported by statistics, and also explored the effects of sea surface temperature rise specific to artisanal fishers.

Met Office, 2011, Climate: Observations, projections and impacts, Peru, Met Office, Exeter

This met office report gave the current state of knowledge regarding climate change in Peru, providing statistics on the population affected and also addressing current uncertainties in future ENSO.

The Royal Society, 2005, Ocean acidification due to increasing atmospheric carbon dioxide, Science policy section, Clyvedon Press Ltd, Cardiff.

This article gave an overview of the effects of ocean acidification and gave specific future projections.

Further References:

Arellano, C. E., and Swartzman G., 2009, The Peruvian artisanal fishery: Changes in patterns and distribution over time, in: Fisheries Research 101 (2010), 133-145)

Bell J. D., Johnson J. E., and Hobday A.J., 2011, Vulnerability of Tropical Pacific Fisheries and Aquaculture to Climate Change, Secretariat of the Pacific Community, Noumea, New Caledonia.

Brooks, N. and Adger, W. N. (2003), Country level risk measures of climate-related natural disasters and implications for adaptation to climate change, Tyndall Centre Working Paper 26:

Chavez, F. P., A. Bertrand, R. Guevara‐Carrasco, P. Soler & J. Csirke. 2008. The northern Humboldt Current system: Brief history, present status and a view towards the future, Prog. Oceanogr., 79, 95-105, doi:10.1016/j.pocean.2008.10.012.

Latif, M., and Keenlyside N. S., 2009, El Nino/Southern Oscillation response to global warming. Proceedings of the National Academy of Sciences of the United States of America, 106, 20578-20583.

Oliver-Smith A, 2009, Sea Level Rise and the Vulnerability of Coastal Peoples: Responding to the Local Challenges of Global Climate Change in the 21st Century, Publication Series of UNU-EHS, Bonn, Germany

Rubio E., 2007, Climate Change Impacts and Adaptation in Peru: The Case of Puno and Piura, Human Development Report Office, occasional paper