Posts Tagged 'socio-economy'

Future marine ecosystem drivers, biodiversity, and fisheries maximum catch potential in Pacific Island countries and territories under climate change

Highlights

  • Under the RCP 8.5 scenario, tropical Pacific temperature will rise by ≥ 3 °C by 2100.
  • This is accompanied by declines in dissolved oxygen, pH, and net primary production.
  • This will lead to local extinctions of up to 80% of marine species in some regions.
  • 9 of 17 Pacific Island entities experience ≥ 50% declines in maximum catch potential.
  • Impacts can be greatly reduced by mitigation measures under the RCP 2.6 scenario.


Abstract

The increase in anthropogenic CO2 emissions over the last century has modified oceanic conditions, affecting marine ecosystems and the goods and services that they provide to society. Pacific Island countries and territories are highly vulnerable to these changes because of their strong dependence on ocean resources, high level of exposure to climate effects, and low adaptive capacity. Projections of mid-to-late 21st century changes in sea surface temperature (SST), dissolved oxygen, pH, and net primary productivity (NPP) were synthesized across the tropical Western Pacific under strong climate mitigation and business-as-usual scenarios. These projections were used to model impacts on marine biodiversity and potential fisheries catches. Results were consistent across three climate models, indicating that SST will rise by ≥ 3 °C, surface dissolved oxygen will decline by ≥ 0.01 ml L−1, pH will drop by ≥ 0.3, and NPP will decrease by 0.5 g m−2 d−1 across much of the region by 2100 under the business-as-usual scenario. These changes were associated with rates of local species extinction of > 50% in many regions as fishes and invertebrates decreased in abundance or migrated to regions with conditions more suitable to their bio-climate envelope. Maximum potential catch (MCP) was projected to decrease by > 50% across many areas, with the largest impacts in the western Pacific warm pool. Climate change scenarios that included strong mitigation resulted in substantial reductions of MCP losses, with the area where MCP losses exceeded 50% reduced from 74.4% of the region under business-as-usual to 36.0% of the region under the strong mitigation scenario.

Continue reading ‘Future marine ecosystem drivers, biodiversity, and fisheries maximum catch potential in Pacific Island countries and territories under climate change’

Evaluation of the ocean ecosystem: Climate change modelling with backstop technologies

This paper discusses the economic impacts of climate change, including those on ecosystems, and whether a new backstop technology should be used under conditions of strict temperature targets. Using the dynamic integrated climate-economy (DICE) model, we developed a new model to calculate the optimal path by considering new backstop technologies, such as CO2 capture and storage (CCS). We identify the effects of parameter changes based on the resulting differences in CO2 leakage and sites, and we analyse the feasibility of CCS. In addition, we focus on ocean acidification and consider the impact on economic activity. As a result, when CCS is assumed to carry a risk of CO2 leakage and acidification is considered to result in a decrease in utility, we find that CCS can only delay the effects of climate change, but its use is necessary to achieve strict targets, such as a 1.5 °C limit. This observation suggests that if the target temperature is too tight, we might end up employing a technology that sacrifices the ecosystem too greatly.

Continue reading ‘Evaluation of the ocean ecosystem: Climate change modelling with backstop technologies’

A good Kiwi isn’t acidic: how ocean acidification is affecting the New Zealand economy

In a country that houses a mere 4 million people, it is no wonder that agriculture has become the main facet of New Zealand’s economy. However, while the sheep and produce have flourished from land protection laws, marine life has struggled in recent years due to an increase in oceanic carbon levels. In an area of the Pacific that is so rich in coral reefs, Great White breeding areas, and a plethora of fish species, any upset of the natural preexisting chemical balance has a tangible impact. New Zealand is dealing with a crisis with huge economic and ecological ramifications. I study the exact adverse effects that ocean acidification has had on the economy of New Zealand. The scientific process of how ocean acidification occurs is a building block of this understanding as well as the Gross Domestic Product (GDP) of the country. The rise of marine pH levels is inextricably linked to the downturn of prosperity in New Zealand’s agricultural sector. My solutions address stricter policies in regards to fishing and emissions regulations to augment the regulation of established New Zealand commercial fishing laws. In this thesis, my goal is to highlight that ocean acidification is a climate problem that affects the entire New Zealand population. By putting these effects into economic terms, I hope to urge change in the “business as usual” way countries conduct themselves, starting with policy makers whose focus is growing their GDP. To illustrate this point effectively, I utilize the disciplines of chemistry, economics, and politics to analyze the trends and consequences of ocean acidification.

Continue reading ‘A good Kiwi isn’t acidic: how ocean acidification is affecting the New Zealand economy’

The influence of ocean acidification on the economic vitality of shellfish hatcheries in the Pacific Northwest: A meta-analysis

Ocean acidification is the chemical process that results in the decrease of ocean pH levels. This decrease is caused by the diffusion of atmospheric carbon dioxide into Earth’s oceans. In other words, Earth’s oceans act as a carbon sink for atmospheric carbon. Prior to the industrial revolution in 1760, the ocean regulated the amount of carbon in earth’s atmosphere in a manner that did not threaten marine ecosystems. However, due to the increased combustion of fossil fuels due to rapid industrialization, urbanization, and population growth, oceans have begun to take up excessive amounts of carbon dioxide, resulting in an alteration of oceanic chemistry. The accumulation of hydrogen ions in ocean water due to the chemical reaction between carbonate carbon dioxide, and water have increased the acidity of the ocean. This has created a corrosive environment for shell-forming organisms that rely on carbonate for their exoskeletons. Many of these organisms, especially those in the Mollusca phylum, are commercially valuable. Ocean acidification has already begun its impact on the shellfish industry in the Pacific Northwest. However, if a business-as-usual scenario of carbon combustion prevails over use of alternative energy sources and mandatory terrestrial pollutant controls, the impact on shellfish aquaculture firms will only intensify and threaten the industry and its associated jobs and revenue. Local, state and federal authorities and agencies have begun to take steps to mitigate the effects of ocean acidification. Mitigation strategies are analyzed on their basis to effectively diminish the physiological and economic impact of ocean acidification on shellfish aquaculture operations. The question remains if these strategies will be able to successfully inhibit the ongoing process of ocean acidification, or simply just delay the impacts.

Continue reading ‘The influence of ocean acidification on the economic vitality of shellfish hatcheries in the Pacific Northwest: A meta-analysis’

Impacts of climate change on fish and shellfish in the coastal and marine environments of Caribbean Small Island Developing States (SIDS)

The commercially important fish and shellfish of Caribbean SIDS have been considered in four groups based on environment and following the typical division of fishery groups used in this region.

There is a dearth of research and long-term datasets on the impacts of climate change on Caribbean marine environments and the important fishery resources. Most research to date has been outside of the Caribbean and has examined the impacts of one or two stressors in short-term ex situ experiments which are unlikely to accurately reflect the true complexity of long-term in situ impacts of climate change in the region. There is a need to consider the combined effects of climate change stressors (direct and indirect) on both individuals and ecosystems, together with the synergistic effects of other chronic anthropogenic stressors in the region.

We consider the reef-associated shallow shelf group to be the most vulnerable of the four fishery groups given: 1) the already apparent negative climate change impacts on their critical habitats; 2) the overexploited state of most reef-associated fishery stocks; 3) the already degraded state of their nearshore habitats as a result of other anthropogenic activities; and 4) their biphasic life history, requiring the ability to settle in specific benthic nursery habitat from a pelagic early life stage.

We consider the most resilient group, over the short-term, to be the oceanic pelagic species that generally show fewer negative responses to the climate change stressors given that they: 1) are highly mobile with generally good acid-base regulation; 2) have an entirely pelagic lifecycle; 3) have less vulnerable reproductive strategies (i.e. they have extended spawning seasons and over broad areas); and 4) are generally exposed to fewer or less severe anthropogenic stressors.

This summary is provided with the following important caveat: “Any attempt to report on what has already happened to fish and shellfish resources in the Caribbean, based on direct evidence, will be strongly biased by the fact that there is a lack of monitoring and directed research examining fish and shellfish species-level impacts of climate change in this region. As such, any conclusions drawn from direct evidence alone will likely misrepresent the true nature and extent of the climate change impacts on the coastal and marine fish and shellfish resources within the Caribbean to date.”

Continue reading ‘Impacts of climate change on fish and shellfish in the coastal and marine environments of Caribbean Small Island Developing States (SIDS)’

Impacts of climate change on coral in the coastal and marine environments of Caribbean Small Island Developing States (SIDS)

Coral reefs are integral to life in the Caribbean – providing protection from storms, sustaining national economies and livelihoods through tourism and fishing, and supporting culture, recreation and biodiversity conservation. Over a decade ago, their value was estimated at US$3.1 – 4.6 billion each year.

Climate change is already impacting coral reefs in the Caribbean, through coral bleaching, disease outbreaks, ocean acidification and physical damage from stronger hurricanes. Coral beaching is the most visible, wide-spread and iconic manifestation of climate change on reefs, with major events in the Caribbean in 1998, 2010 and 2015/16. The extent of bleaching and associated mortality varies by location and event, but has resulted in some mortality. Coral disease has already significantly altered the community composition of reefs in the Caribbean, and is projected to result in increasing frequency of outbreaks as seas warm. The lack of a centralized database to coordinate reef monitoring information, hampers efforts to measure these effects.

Ocean acidification is a direct chemical result of increased carbon dioxide, but it has a variety of different responses in different reef organisms. Corals are the brick foundations of the reef, with crustose coralline algae as their mortar. Both these critical functional groups are already being affected by the reduced pH of surface water, making it more difficult to calcify and grow.

Future impacts are expected to follow and accelerate on these trends.

By 2040–2043 projections are for the onset of annual severe bleaching, which would likely result in significant coral mortality. Disease outbreaks are predicted to become annual events several years earlier. Projections for future ocean acidification result in ocean carbonate saturation levels potentially dropping below those required to sustain coral reef accretion by 2050. Cutting emissions in CO2 (within RCP6.0) would buy many coral reefs a couple of decades more time before the worst impacts occur, but it delays rather than mitigates the threats posed to coral reefs by acidification and bleaching (Maynard et al, 2016).

National leaders of the Caribbean need to adamantly fight for CO2 emissions reductions, and ensure their reef management agencies take all precautionary measures needed to reduce local stress on their reefs to buy them additional time and resiliency potential for withstanding the stress of climate change.

Continue reading ‘Impacts of climate change on coral in the coastal and marine environments of Caribbean Small Island Developing States (SIDS)’

The social cost of carbon

The social cost of carbon (SCC) provides a monetary measure of the net global harm resulting from a small increase in atmospheric carbon dioxide. Conversely, it also measures the net reduction in harm (social benefit) from a decrease. Federal agencies in the United States have developed a range of estimates of the SCC, with core values that anticipate net costs of about $50 per metric ton for emissions of carbon dioxide in the next few years, rising to about $80 for mid-century emissions. These estimates embody considerable uncertainty, and multiple factors indicate the actual SCC is probably several hundred dollars per ton. Those seeking to promote sustainable improvements in human wellbeing should forgo actions that would increase atmospheric carbon dioxide—or other greenhouse gasses with equivalent effects—unless they can yield benefits that more than offset these costs.

Continue reading ‘The social cost of carbon’


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OA-ICC HIGHLIGHTS

Ocean acidification in the IPCC AR5 WG II

OUP book