Pacific Climate Change Projections and Scenario Assumptions

In the absence of complete information and perfect stochastic forecasting capabilities towards the projected impact of climate change in the Pacific, research such as Gero et al. (2013) and Goodrich et al. (2015), has traditionally focussed on modelling projected risks, associated impact costs and consequences with underlying assumptions. These sources aim to provide supply chain stakeholders with specific guidance over which adaptation actions to prioritise pre and post-disruption event and where to efficaciously allocate resources. The assumptions below and scenarios are based on the above sources, and an ever increasing, substantial number of research sources (World Bank 2012; International Climate Change Adaptation Initiative 2013; Australia Bureau of Meteorology and CSIRO 2014; World Meteorological Organisation 2015). These assumptions possess a significant number of research advantages to satisfy maritime supply chain stakeholder requirements of sufficient information, flexibility, available and consistently updated. This paper’s conceptual contribution to existing literature establishes the following assumptions accepted to present direct sudden and gradual climate change disruption threats towards the future survival of maritime supply chains, particularly in the Pacific. The potential threat of climate change for Pacific maritime supply chain stakeholders, further justifies the need for tools, screening criteria and other solutions, to enable climate change adaptation at minimal opportunity cost across divergent climate change methods (Fig. 12.1).

Fig. 12.1 Historic CO₂ emissions scenario growth

These produce the following gradual climate change disruption risk

consequences

• • An increase in global average land surface, atmosphere and sea level temperature levels, of 1.5-2 °C (B1 scenario), even if emissions were to cease based on historic inventory levels.
• • An increase of 2.5-4 °C (IPCC 2015 A1B scenario) if emissions are stabilised at the current medium growth rate by 2100.
• • Increases of 4-7 °C (IPCC 2015 A2 scenario) if emissions are not reduced.
• • A 0.5 m global average sea level rise is projected for a low risk, current growth, scenario where emissions are highly reduced, 0.8 m rise—medium risk if emissions are stabilised and up to 1.1 m high for a high risk, continued emissions increase scenario by 2100, in pursuing current global GDP growth rates of 3-5% annually.
• • Other anticipated gradual global, Pacific regional and individual increases in sea level, temperature, humidity, precipitation and wind speed along with potential variations in wind direction, current, ocean swell, wave energy and sedimentation, as gradual climate change disruption risks.
• • Greenhouse gas CO₂ emissions would have to stabilise around 450 (ppm) (430480) at present; no higher than 550 ppm (530-580) by 2100, to ensure this.
• • A projected increase in the frequency, duration and intensity of sudden climate-change related natural disaster disruption risks including storms, flooding, superstorms, tsunamis, hurricanes, typhoons, heatwaves and landslides, with higher precipitation and wind speeds.

This section refers to the three most common scenarios that Pacific and other maritime supply chain stakeholders are likely to encounter when accessing divergent research sources, methodologies and adaptation solutions: B1, A1B and A2 scenarios over 3 time horizons. B1 is used by the IPCC (2015) and international climate change policy makers (Pacific Islands Forum Secretariat 2012; Pacific Island Climate Change Cooperative 2015; SPREP and UNDP 2015) to refer to a low greenhouse gas emissions growth scenario, if humanity were to become substantially more environmentally sustainable, convert from an industrial to a services based economy less resource and greenhouse gas emissions intensive and restricting population growth to reduce emissions. A1B refers to a medium emissions growth scenario or “business as usual” if population and economic activity were to continue at current growth levels. A2 refers to a projected high emissions growth scenario if developing countries don’t stabilise population, dramatically reduce emissions and pursue globalisation economic activity levels of developed nations. The three projected time horizons (2030, 2055 and 2090) are advised by IPCC (2015) to consider as short, medium and long term periods for maritime supply chain stakeholders to adapt.

Based on IPCC (2015) data estimates and Fig. 12.2, global mean surface temperature rises are projected to increase from a baseline of 0 °C in 2000 to 0.85° by 2030 under all 3 scenarios. However by 2055, emissions are projected to diverge, around 1.2° under a B1, 1.59° for an A1B and 1.86° for an A2 scenario, increasing to an average of 2, 3 and 4.5° respectively by a 2100 long term projection. Figure 12.3 provides an alternative visual representation of how specific world regions will be affected and vulnerable under an A2 scenario. Increased global mean temperature implications for maritime supply chains are indicated throughout this paper possessing significant climate change disruption risks, direct and indirect impact/adaptation costs. Higher temperatures contribute towards an increased frequency of droughts, greater maximum and minimum temperatures; reduced water; higher evaporation and evapotranspiration rates, affecting future climates, natural resources and productivity, (Simpson et al. 2007; Collins et al. 2010; Matear 2014).

Fig. 12.2 Global mean surface temperature, climate change projections

Climate change projections may include slower ocean currents/thermohaline circulation, complicating navigation. These projections illustrate how vital it is for these stakeholders globally to adapt, enhancing vessel and infrastructure resilience to higher temperatures and increased salinity.

IPCC (2015) data estimates in Fig. 12.3, estimate historic global average sea level rise rose from a 0 m baseline in 1900 to 0.030 m by 2000. The rate of increase has substantially accelerated from an average of 1-1.5 mm per year (1900-1980) (Australia Bureau of Meteorology 2015) to 3-3.5 mm per year (1980-2014) and is projected to reach up to 8-10 mm per year by 2100, if global climate change trends are not stabilised. From IPCC (2015) data and Figs. 12.4 and 12.5, global mean sea level rises are projected to increase from a 0 baseline in 2000 under all 3 scenarios. However by 2030, scenarios are projected to diverge around 0.12 m under a B1, 0.16 for an A1B and 0.33 m for an A2 scenario, increasing to an average of 0.23, 0.3 and 0.62 m respectively by 2055 By 2100, maritime supply chain stakeholders are anticipated to experience a projected mean sea level rise of 0.6 (B1), 0.8 (A1B) and 1.5 m.

Fig. 12.3 Projected climate change, surface temperature changes 1999-2090. Source Encyclopaedia Britannica (2008), p. 72

Fig. 12.4 Historic average global sea level rise 1900-2000

Fig. 12.5 Global sea level rise, climate change risk projections