How much ocean surface change is expected under RCP8.5 by 2100?

Question

Accepted Answer

Up to 95 Percent of Ocean Surface Conditions Could Disappear by 2100 Under High Emissions Scenario

By the end of the century, as much as 95 per cent of the Earth’s ocean surface conditions present throughout the 20th century may cease to exist if carbon emissions continue to rise unabated. This projection is based on the RCP8.5 scenario, which assumes a "business as usual" approach with ongoing increases in emissions over the next 80 years. Furthermore, under this high emissions pathway, up to 82 per cent of the ocean surface could experience climates that are unprecedented in recent human history.
Disappearance of 20th Century Ocean Climates

Under the RCP8.5 scenario, which models a future where greenhouse gas emissions continue to climb throughout the next eight decades, a significant portion of the ocean's existing surface climates is projected to vanish. Specifically, research indicates that 95 per cent of the ocean surface conditions that were characteristic of the 20th century are likely to be replaced by new environmental states by the year 2100. This scenario contrasts with the RCP4.5 pathway, which anticipates a peak in emissions around 2050 followed by a gradual decline, under which only 36 percent of 20th-century ocean surface conditions are expected to disappear.
Emergence of Novel Ocean Climates

Beyond the disappearance of familiar conditions, the RCP8.5 scenario also forecasts the emergence of entirely new climatic regimes across the ocean surface. By 2100, the research suggests that up to 82 per cent of the ocean surface may be subject to conditions that have not been observed in recent history. These novel climates are characterised by increased water temperature, heightened acidity, and reduced concentrations of vital minerals like aragonite, which many marine organisms depend on for skeletal and shell formation.
Impact on Marine Life

The changing ocean surface conditions have profound implications for the vast array of sea life that inhabits these environments. Ocean surface climates, defined by factors such as temperature, acidity, and aragonite concentration, are fundamental to supporting marine ecosystems. As these conditions shift dramatically, species that are narrowly adapted to current environments will face significant challenges in adapting to the altered chemistry and temperature of the water.
Limited Options for Marine Species

While some marine species have historically been able to migrate to more favourable conditions, the projected near-uniform warming and acidification under the RCP8.5 scenario may limit these options. The study indicates that the communities of species found in specific areas will likely continue to shift and change rapidly in the coming decades. The lead author noted that a climate which is common today could become rare or absent in the future, forcing species to adapt to conditions that are increasingly widespread globally.

Reading history

Hide →

This history is cleared when the page is closed.

How much ocean surface change is expected under RCP8.5 by 2100?

Loading

Was this article helpful?

Helpful

Not helpful

Report an issue

1

0

0

Share with friends