Sea-level rise trajectories by 2200 with warming of 1.5 to 2°C

S. Jevrejeva, D.F. Hendry, F. Mir Calafat and L. P. Jackson

The impact of sea-level rise is already felt

Jakarta already experiences significant coastal flooding due to seasonal high-tides coupled with subsidence

Sea level is the sum of many parts

The sea level you see anywhere in the world is the sum of a set components:

Global Regional

Sea level Land waterAntarcticaGreenlandGlaciersExpansion

Sea level is the sum of many parts

The sea level you see anywhere in the world is the sum of a set components:

Global Regional

Sea level Land waterAntarcticaGreenlandGlaciersExpansion

Sum of components

Observations

From Gregory et al. (2013)

Sea level is the sum of many parts

The sea level you see anywhere in the world is the sum of a set components:

Global Regional

Sea level Land waterAntarcticaGreenlandGlaciersExpansion

Sum of components

Observations

From Gregory et al. (2013)

Periodcovered (years)

Rate of global sea-level (mm/yr)

6,000 BC –1880 AD

0.3

1880 – 1992 1.8

1992 – 2017 3.4

Sea level is the sum of many parts

Where you are matters: each component has a unique spatial pattern

Currents

Global Regional Local

Sea level Land waterAntarcticaGreenlandGlaciersExpansion Uplift/subside

Making projections for Paris

Jackson et al. (2018)

Select temperature pathways from

CMIP5 models (RCP 2.6 and RCP 4.5)

conforming to Paris thresholds by end-

of-century

Global sea-level projections for Paris

Jackson et al. (2018)

Fan shows different levels of probability

Global sea-level projections for Paris

Jackson et al. (2018)

Each component contributes to a different amount of uncertainty

Regional sea-level projections for Paris

Jackson et al. (2018)

Paris (1.5°C) Paris (2.0°C)

Most parts of the ocean experience a

sea level rise within ±20% of global average

Paris versus Business-as-Usual

Jevrejeva et al. (2018)

Paris (1.5°C)

Business-as-usual (>4°C)

Consensus across pathways as to sea level rise by mid-century

Present global and national climate response to emissions will

impact sea level pathway in second-half of century

Paris versus Business-as-Usual

Jevrejeva et al. (2018)

Deep uncertainty about the future of the polar ice sheets for high-end

projections

Paris versus Business-as-Usual

Jevrejeva et al. (2018)

Estimate country level coastal flood damages using global average sea level rise and present-day local

extreme sea levels

UK flood cost in 2100 (no further adaptation)US$ 241 billion per year (2.5 % UK GDP) with warming of 1.5 degree (median, 0. 5 m sea level rise)

US$ 619 billion per year (6.5% UK GDP) with RCP8.5 (median, 0. 8 m sea level rise)US$ 1.1. trillion per year (11.1 % UK GDP) with RCP8.5 (95%, 1.8 m sea level rise)

Global Sea flood cost,Million US$ per year

Global Sea flood cost, % of GDP (global)

UK Sea flood cost,% of UK GDP

Implications: sea flood damage costs

Jevrejeva et al. (2018)

Beyond damages: wider sea-level implications

International Law of the Sea

[e.g. Schofield & Freestone, 2013]

Beyond damages: wider sea-level implications

International Law of the Sea Transport and Communications infrastructure

[e.g. Internet infrastructure: Durairajan et al. 2018]

[e.g. Schofield & Freestone, 2013]

Beyond damages: wider sea-level implications

International Law of the Sea Transport and Communications infrastructure

[e.g. Internet infrastructure: Durairajan et al. 2018]

[e.g. Schofield & Freestone, 2013]

Combined mitigation and adaptation strategies [e.g. Blue Carbon: Doughty et al. 2017]

Beyond damages: wider sea-level implications

International Law of the Sea Transport and Communications infrastructure

[e.g. Internet infrastructure: Durairajan et al. 2018]

[e.g. Schofield & Freestone, 2013]

Combined mitigation and adaptation strategies [e.g. Blue Carbon: Doughty et al. 2017]

Human health and well-being[e.g. Patz et al. 2005]

Thank youConclusions

• Sea-level rise is already affecting many coastal populations worldwide

• Future sea-level change is intrinsically linked to our current and future climate.• Sea-level change is a long term inertial process that is likely to continue rising well after

2100, even under strong mitigation.

• There is consensus across scenarios that global sea level will rise by ~25 cm (rel. to 1995) by mid-century.

• There remains deep uncertainty about the future mass loss of the polar ice sheets.

• As sea level rises, coastal flooding will become more intense, more frequent and more costly (up to 11% UK GDP without further adaptation).

• Implications arising from present and future sea-level rise include- Territorial definitions- Damage to coastal infrastructure- Adaptation strategies that embed mitigation- Human health and well-being

Thank youPublications

Jackson, L.P., Grinsted, A. and Jevrejeva, S., 2018. 21st Century Sea‐Level Rise in Line with the Paris Accord. Earth's Future, 6(2), pp.213-229. Doi: 10.1002/2017EF000688

Jevrejeva, S., Jackson, L.P., Grinsted, A., Lincke, D. and Marzeion, B., 2018. Flood damage costs under the sea level rise with warming of 1.5° C and 2° C. Environmental Research Letters, 13(7), p.074014. Doi: 10.1088/1748-9326/aacc76