From days to decades: numerical modeling of freshwater lens response to climate change stressors on small islands

Abstract. Freshwater lenses on small islands are vulnerable to many climate change related stressors, which can act over relatively long time periods, on the order of decades (e.g. sea level rise, changes in recharge), or short time periods, such as days (storm surge overwash). This study evaluates response of the freshwater lens on a small low-lying island to various stressors. To account for the varying temporal and spatial scales of the stressors, two different density-dependent flow and solute transport codes are used: SEAWAT and HydroGeoSphere. The study site is Andros Island in the Bahamas, which is characteristic of other low-lying carbonate islands in the Caribbean and South Pacific regions. In addition to projected sea level rise and reduced recharge under future climate change, Andros Island experienced a storm surge overwash event during Hurricane Francis in 2004, which contaminated the main wellfield. Simulations of reduced recharge result in up to 19% loss of freshwater lens volume, while sea level rise contributes up to 5% volume loss. The lens responds relatively quickly to these stressors, within 0.5 to 3 years. Simulations of the storm surge overwash indicate that the freshwater lens recovers over time; however, prompt remedial action can restore the lens to potable concentrations up to one month sooner.

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From days to decades: numerical modelling of freshwater lens response to climate change stressors on small low-lying islands

Hydrology and Earth System Sciences ◽

10.5194/hess-19-933-2015 ◽

2015 ◽

Vol 19 (2) ◽

pp. 933-949 ◽

Cited By ~ 29

Author(s):

S. Holding ◽

D. M. Allen

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Storm Surge ◽

Spatial Scales ◽

Future Climate Change ◽

Freshwater Lens ◽

Andros Island ◽

Time Periods ◽

The Impact

Abstract. Freshwater lenses on small islands are vulnerable to many climate change-related stressors, which can act over relatively long time periods, on the order of decades (e.g., sea level rise, changes in recharge), or short time periods, such as days (storm surge overwash). This study evaluates the response of the freshwater lens on a small low-lying island to various stressors. To account for the varying temporal and spatial scales of the stressors, two different density-dependent flow and solute transport codes are used: SEAWAT (saturated) and HydroGeoSphere (unsaturated/saturated). The study site is Andros Island in the Bahamas, which is characteristic of other low-lying carbonate islands in the Caribbean and Pacific regions. In addition to projected sea level rise and reduced recharge under future climate change, Andros Island experienced a storm surge overwash event during Hurricane Francis in 2004, which contaminated the main wellfield. Simulations of reduced recharge result in a greater loss of freshwater lens volume (up to 19%), while sea level rise contributes a lower volume loss (up to 5%) due to the flux-controlled conceptualization of Andros Island, which limits the impact of sea level rise. Reduced recharge and sea level rise were simulated as incremental instantaneous shifts. The lens responds relatively quickly to these stressors, within 0.5 to 3 years, with response time increasing as the magnitude of the stressor increases. Simulations of the storm surge overwash indicate that the freshwater lens recovers over time; however, prompt remedial action can restore the lens to potable concentrations up to 1 month sooner.

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Rising Sea Level, Receding Boundaries and Freezing Baselines in a Warming Climate

Current Journal of Applied Science and Technology ◽

10.9734/cjast/2019/v36i630260 ◽

2019 ◽

pp. 1-7

Author(s):

Emojong Amai Mercy ◽

Eliud Garry Michura

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Future Climate Change ◽

Maritime Boundary ◽

Climate Change Effect ◽

Global Sea Level ◽

Comprehensive Framework ◽

Maritime Boundary Delimitation ◽

International Boundaries

This paper discusses the less publicised but far from less significant, an issue of how the international community’s approach to maritime boundary delimitation will be impacted by climate change resulting in sea level rise with coastal lands submerging affecting the international boundaries and impacting on biodiversity and human survival in the future. The climate change effect is already creating pressure on international law regardless of the direction that the law of the sea takes in remedying this dilemma. It is quite apparent that global disputes and conflicts are arising and solutions are needed urgently. The climate change and the consequent global sea level rise are widely touted to submerge islands and coastlines without discrimination. The international community has been relatively slow to react to what could pose an unprecedented threat to human civilisation. The policies that have been applied have arguably been reactive and not proactive. In future climate change may develop other by-products which may not be understood at this moment and may require a proactive approach. Further discussion of the merits of the potential paths is ideal in ensuring that appropriate and well thought-out resolutions are negotiated. Regardless of the outcome, the thorough debate is required to ensure the correct decision is made and that the balancing act between fulfilling states' interests and achieving a meaningful result does not become detrimental to the solidity and the enforceability of the outcome. There is a need to establish a comprehensive framework for ocean governance for management and long-term development and sustainability.

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Earth's energy imbalance and implications

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-13421-2011 ◽

2011 ◽

Vol 11 (24) ◽

pp. 13421-13449 ◽

Cited By ~ 311

Author(s):

J. Hansen ◽

M. Sato ◽

P. Kharecha ◽

K. von Schuckmann

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Solar Minimum ◽

Climate Forcing ◽

Future Climate Change ◽

Ocean Heat Uptake ◽

Surface Temperature Change ◽

Energy Imbalance ◽

Ice Melt

Abstract. Improving observations of ocean heat content show that Earth is absorbing more energy from the Sun than it is radiating to space as heat, even during the recent solar minimum. The inferred planetary energy imbalance, 0.58 ± 0.15 W m−2 during the 6-yr period 2005–2010, confirms the dominant role of the human-made greenhouse effect in driving global climate change. Observed surface temperature change and ocean heat gain together constrain the net climate forcing and ocean mixing rates. We conclude that most climate models mix heat too efficiently into the deep ocean and as a result underestimate the negative forcing by human-made aerosols. Aerosol climate forcing today is inferred to be −1.6 ± 0.3 W m−2, implying substantial aerosol indirect climate forcing via cloud changes. Continued failure to quantify the specific origins of this large forcing is untenable, as knowledge of changing aerosol effects is needed to understand future climate change. We conclude that recent slowdown of ocean heat uptake was caused by a delayed rebound effect from Mount Pinatubo aerosols and a deep prolonged solar minimum. Observed sea level rise during the Argo float era is readily accounted for by ice melt and ocean thermal expansion, but the ascendency of ice melt leads us to anticipate acceleration of the rate of sea level rise this decade.

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Risk to North American Birds from Climate Change-Related Threats

10.1101/798694 ◽

2019 ◽

Author(s):

Brooke L. Bateman ◽

Lotem Taylor ◽

Chad Wilsey ◽

Joanna Wu ◽

Geoffrey S. LeBaron ◽

...

Keyword(s):

Climate Change ◽

United States ◽

Species Richness ◽

Sea Level Rise ◽

Sea Level ◽

Extreme Weather ◽

Extreme Weather Events ◽

Future Climate Change ◽

Individual Species ◽

Weather Events

AbstractClimate change is a significant threat to biodiversity globally, compounded by threats that could hinder species’ ability to respond through range shifts. However, little research has examined how future bird ranges may coincide with multiple stressors at a broad scale. Here, we assess the risk to 544 birds in the United States from future climate change threats under a mitigation-dependent global warming scenario of 1.5°C and an unmitigated scenario of 3.0°C. Threats considered included sea level rise, lake level change, human land cover conversion, and extreme weather events. We developed a gridded index of risk based on coincident threats, species richness, and richness of vulnerable species. To assign risk to individual species and habitat groups, we overlaid future bird ranges with threats to calculate the proportion of species’ ranges affected in both the breeding and non-breeding seasons. Nearly all species will face at least one new climate-related threat in each season and scenario analyzed. Even with lower species richness, the 3.0°C scenario had higher risk for species and groups in both seasons. With unmitigated climate change, multiple coincident threats will affect over 88% of the conterminous United States, and 97% of species could be affected by two or more climate-related threats. Some habitat groups will see up to 96% species facing three or more threats. However, climate change mitigation would reduce risk to birds from climate change-related threats across over 90% of the US. Across the threats included here, extreme weather events have the most significant influence on risk and the most extensive spatial coverage. Urbanization and sea level rise will also have disproportionate impacts on species relative to the area they cover. By incorporating threats into predictions of climate change impacts, this assessment provides a comprehensive picture of how climate change will affect birds and the places they need.

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INVESTIGATION OF IMPACTS OF SEA-LEVEL RISE, STORM SURGE AND CLIMATE CHANGE ON MARITIME FORESTS ADJACENT TO CHINCOTEAGUE BAY, VIRGINIA USING DENDROECOLOGY TREE RING ANALYSIS

10.1130/abs/2018ne-311363 ◽

2018 ◽

Author(s):

Olivia Allen ◽

◽

Sean R. Cornell

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Storm Surge ◽

Tree Ring ◽

Tree Ring Analysis ◽

Ring Analysis ◽

Chincoteague Bay

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Analysis of Flood Vulnerability and Transit Availability with a Changing Climate in Harris County, Texas

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198119839346 ◽

2019 ◽

Vol 2673 (6) ◽

pp. 258-266 ◽

Cited By ~ 4

Author(s):

Joshua A. Pulcinella ◽

Arne M. E. Winguth ◽

Diane Jones Allen ◽

Niveditha Dasa Gangadhar

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Storm Surge ◽

Extreme Weather ◽

Extreme Weather Events ◽

Harris County ◽

Weather Events ◽

Block Groups ◽

The Impact

Hurricanes and other extreme precipitation events can have devastating effects on population and infrastructure that can create problems for emergency responses and evacuation. Projected climate change and associated global warming may lead to an increase in extreme weather events that results in greater inundation from storm surges or massive precipitation. For example, record flooding during Hurricane Katrina or, more recently, during Hurricane Harvey in 2017, led to many people being cut off from aid and unable to evacuate. This study focuses on the impact of severe weather under climate change for areas of Harris County, TX that are susceptible to flooding either by storm surge or extreme rainfall and evaluates the transit demand and availability in those areas. Future risk of flooding in Harris County was assessed by GIS mapping of the 100-year and 500-year FEMA floodplains and most extreme category 5 storm tide and global sea level rise. The flood maps have been overlaid with population demographics and transit accessibility to determine vulnerable populations in need of transit during a disaster. It was calculated that 70% of densely populated census block groups are located within the floodplains, including a disproportional amount of low-income block groups. The results also show a lack of transit availability in many areas susceptible to extreme storm surge exaggerated with sea level rise. Further study of these areas to improve transit infrastructure and evacuation strategies will improve the outcomes of extreme weather events in the future.

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Estuarine response to river flow and sea-level rise under future climate change and human development

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2014.08.015 ◽

2015 ◽

Vol 156 ◽

pp. 19-30 ◽

Cited By ~ 56

Author(s):

Zhaoqing Yang ◽

Taiping Wang ◽

Nathalie Voisin ◽

Andrea Copping

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Human Development ◽

Sea Level ◽

River Flow ◽

Future Climate ◽

Future Climate Change ◽

And Sea Level

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Developing future sea level services for Small Island Developing States

10.5194/egusphere-egu2020-6495 ◽

2020 ◽

Author(s):

Svetlana Jevrejeva ◽

Judith Wolf ◽

Andy Matthews ◽

Joanne Williams ◽

David Byrne ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Water Level ◽

Sea Level ◽

Future Climate Change ◽

Small Island ◽

Caribbean Region ◽

Caribbean Islands ◽

The Caribbean ◽

And Sea Level

The Caribbean islands encompass some of the most vulnerable coastlines in terms of sea level rise, exposure to tropical cyclones, changes in waves and storm surges. Climate in the Caribbean is already changing and sea level rise impacts are already being felt. Considerable local and regional variations in the rate, magnitude, and direction of sea-level change can be expected as a result of thermal expansion, tectonic movements, and changes in ocean circulation. Governments in the Caribbean recognise that climate change and sea level rise are serious threats to the sustainable development and economic growth of the Caribbean islands and urgent actions are required to increase the resilience and make decisions about how to adapt to future climate change (Caribbean Marine Climate Change Report Card 2017; IPCC 2014).As part of the UK Commonwealth Marine Economies (CME) Programme and through collaboration with local stakeholders in St Vincent, we have identified particular areas at risk from changing water level and wave conditions. The Caribbean Sea, particularly the Lesser Antilles, suffers from limited observational data due to a lack of coastal monitoring, making numerical models even more important to fill this gap. The current projects brings together improved access to tide gauge observations, as well as global, regional and local water level and wave modelling to provide useful tools for coastal planners.We present our initial design of a coastal data hub with sea level information for stakeholder access in St. Vincent and Grenadines, Grenada and St Lucia, with potential development of the hub for the Caribbean region. The work presented here is a contribution to the wide range of ongoing activities under the Commonwealth Marine Economies (CME) Programme in the Caribbean, falling within the work package &#8220;Development of a coastal data hub for stakeholder access in the Caribbean region&#8221;, under the NOC led projects &#8220;Climate Change Impact Assessment: Ocean Modelling and Monitoring for the Caribbean CME states&#8221;.

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