Influence of CO2-induced acidification on the reproduction of a key Arctic copepod Calanus glacialis

The Arctic Ocean is facing rapid changes in seawater carbonate chemistry due to the uptake of atmospheric carbon dioxide (CO₂). In the current study, the effects of different seawater pH levels (8.2, 7.6 and 6.9) on the reproduction of Calanus glacialis, an Arctic shelf-water copepod, have been quantified. Results indicated that CO₂-induced seawater acidification had no significant effect on C. glacialis egg production. However, a reduction in pH to 6.9 significantly delayed hatching and possibly reduced overall hatching success. The results of the current study are in agreement with previous studies on other copepod species and would indicate that copepods, as a group, may be well equipped to deal with the chemical changes associated with ocean acidification. However, all previous studies have been over relatively short exposure periods and most have only considered the isolated impacts of elevated CO₂. Long-term exposures examining the synergistic effects of ocean acidification with other climate stressors, particularly warming on population viability and success, have yet to be conducted.

The likelihood and potential impact of future change in the large-scale climate-earth system on ecosystem services

This article reviews the level of current scientific understanding regarding the impact of future change in the large-scale climate-earth system on ecosystem services. Impacts from sea level rise, ocean acidification, increases in ocean temperature, potential collapse of the thermohaline circulation; failure of the South Asia monsoon; the melting of sea ice, the Greenland Ice Sheet and the West Antarctic Ice Sheet; changes in water availability; and Amazonia forest dieback, are considered. The review highlights that while a number of uncertainties remain in understanding, there is evidence to suggest that climate change may have already affected some ecosystem services. Furthermore, there is considerable evidence to show that future climate change could have impacts on biodiversity, as well as secondary impacts on issues important to human society, including; habitability; land productivity and food security; water security; and potential economic impacts.

Flourishing seaweed

Macroalgae (seaweed) form an important component of rocky shore ecosystems, so an understanding of their sensitivity to ocean acidification is important for understanding the wider ocean acidification impacts on coastal ecosystems.