Ocean Acidification in a Rapidly Increasing CO2 World. Carbon dioxide not only acts as a greenhouse gas but is being dissolved at increasing rates into the surface waters of the world's oceans, causing ocean acidity. We will examine how the rapidly increasing trend towards acidity in the oceans surrounding Australia is effecting the ability of marine organisms to calcify and determine the rate at which the world's ocean sink for CO2 is being reduced. New constraints will be placed on the critica ....Ocean Acidification in a Rapidly Increasing CO2 World. Carbon dioxide not only acts as a greenhouse gas but is being dissolved at increasing rates into the surface waters of the world's oceans, causing ocean acidity. We will examine how the rapidly increasing trend towards acidity in the oceans surrounding Australia is effecting the ability of marine organisms to calcify and determine the rate at which the world's ocean sink for CO2 is being reduced. New constraints will be placed on the critical threshold limits of CO2 emissions for sustainable calcification in both shallow tropical and deep-water marine ecosystems of the Southern Oceans.Read moreRead less
Enhanced Weathering – a sustainable tool for CO2 Removal? This project aims to be the first to assess risks and co-benefits of Enhanced Weathering for marine pelagic ecosystems. Enhanced Weathering is a powerful tool that can reduce atmospheric CO2 with significant economic co-benefits. However, it perturbs seawater chemistry and associated impacts on marine ecosystems are unknown. This project expects to combine state-of-the-art field and laboratory research to reveal whether Enhanced Weatherin ....Enhanced Weathering – a sustainable tool for CO2 Removal? This project aims to be the first to assess risks and co-benefits of Enhanced Weathering for marine pelagic ecosystems. Enhanced Weathering is a powerful tool that can reduce atmospheric CO2 with significant economic co-benefits. However, it perturbs seawater chemistry and associated impacts on marine ecosystems are unknown. This project expects to combine state-of-the-art field and laboratory research to reveal whether Enhanced Weathering is a sustainable tool for CO2 Removal. The project provides significant benefits as it builds capacity within the currently emerging research field “ocean-based climate change solutions”. Within this capacity, it will help to identify a sustainable and economically viable future for Australia.Read moreRead less
Keystone microbes and planktonic guilds in Australia's oceans. This project aims to unveil the ocean’s hidden sentinels, “keystone microbes” that underpin precious ecosystem services, and which can be used to monitor and model changes in ocean function. Marine microbes account for 90 per cent of oceanic biomass and every litre of seawater contains ~20,000 different species, but it is not known which species control ocean health and productivity. This project intends to provide definitive evidenc ....Keystone microbes and planktonic guilds in Australia's oceans. This project aims to unveil the ocean’s hidden sentinels, “keystone microbes” that underpin precious ecosystem services, and which can be used to monitor and model changes in ocean function. Marine microbes account for 90 per cent of oceanic biomass and every litre of seawater contains ~20,000 different species, but it is not known which species control ocean health and productivity. This project intends to provide definitive evidence of these keystones’ cellular level biogeochemical and metabolic capacity. Ultimately, this knowledge is expected to predict the resilience of ocean ecosystems and their response to change. The capacity to predict their dynamics will help provide investment clarity and increase healthy outcomes from activities involving human-ocean interactions such as recreation, food production and tourism.Read moreRead less
The krill pump: transferring carbon across a layered ocean in a changing climate. Krill may have an important role in temperate oceanic ecosystems, and rise to the surface to feed at dusk, competing with other zooplankton and being eaten by commercial fish species. Their response to a rapidly warming ocean is a key unknown, especially with currents off eastern Australia warming 2.5 degrees Celsius by 2100.
Indian Ocean Climate Change: Ningaloo Reef, a litmus test for the survival of coral reefs. Coral reefs are at the frontline from the effects of rapidly rising levels of carbon dioxide that is causing both global warming and oceans to become more acid-like. Our research program will determine how the survival of one of the World’s most pristine and best preserved coral reefs, Ningaloo Reef, is linked to the response of Australia’s Indian Ocean to climate change. For the first time, we will simula ....Indian Ocean Climate Change: Ningaloo Reef, a litmus test for the survival of coral reefs. Coral reefs are at the frontline from the effects of rapidly rising levels of carbon dioxide that is causing both global warming and oceans to become more acid-like. Our research program will determine how the survival of one of the World’s most pristine and best preserved coral reefs, Ningaloo Reef, is linked to the response of Australia’s Indian Ocean to climate change. For the first time, we will simulate realistic ‘future’ conditions and see how actual coral reef systems respond. This will provide a ‘yardstick’ against which the best-case survival potential of the world’s coral reefs can be assessed, critical for underpinning the urgently needed action to reduce greenhouse gas emissions if we are to ensure the survival of coral reefs.Read moreRead less
Holding coral reefs together with soluble cement. This project aims to characterise and understand cement formation in coral reefs. Coral reefs are constructed by cementing together aragonite building blocks made by corals. The main cementing agent is high-magnesium calcite, the most soluble carbonate mineral and susceptible to ocean acidification. High-magnesium calcite cements are best developed on the high energy margins of coral reefs. This project will quantify how crustose coralline algae ....Holding coral reefs together with soluble cement. This project aims to characterise and understand cement formation in coral reefs. Coral reefs are constructed by cementing together aragonite building blocks made by corals. The main cementing agent is high-magnesium calcite, the most soluble carbonate mineral and susceptible to ocean acidification. High-magnesium calcite cements are best developed on the high energy margins of coral reefs. This project will quantify how crustose coralline algae produces high-magnesium calcite and controls the dissolution and reprecipitation of high-magnesium cements. This project intends to quantify rates of reef cementation, susceptibility to ocean acidification and warming, and possible mitigating effects of alkalinity addition.Read moreRead less
The Southern Ocean Meridional Overturning Circulation: New observations of vertical mixing. The Southern Ocean and Antarctic Circumpolar Current (ACC) play profound roles in Australian and global climate. However, we know little about how they will be affected by global warming. New velocity observations will tell us how the vertical mixing that contributes to the meridional overturning circulation, and ACC strength, change with the seasons and from year to year. The observations will also gi ....The Southern Ocean Meridional Overturning Circulation: New observations of vertical mixing. The Southern Ocean and Antarctic Circumpolar Current (ACC) play profound roles in Australian and global climate. However, we know little about how they will be affected by global warming. New velocity observations will tell us how the vertical mixing that contributes to the meridional overturning circulation, and ACC strength, change with the seasons and from year to year. The observations will also give us a better understanding of the oceanic and atmospheric processes that drive these changes. This new information will allow climate models to be better constrained so they can more accurately predict changes to Australian and global climate.Read moreRead less
Causes of Enhanced Warming of the Southern Ocean. The Southern Ocean is critical to the global climate system in general, and Australian climate in particular. However, the Southern Ocean is poorly understood, poorly observed and poorly modelled by global climate models. The response of the Southern Ocean to increases in wind forcing (due to the ozone hole and global warming) will be examined. Climate impacts such as Australian rainfall trends, potential instability of the West Antarctic Ice She ....Causes of Enhanced Warming of the Southern Ocean. The Southern Ocean is critical to the global climate system in general, and Australian climate in particular. However, the Southern Ocean is poorly understood, poorly observed and poorly modelled by global climate models. The response of the Southern Ocean to increases in wind forcing (due to the ozone hole and global warming) will be examined. Climate impacts such as Australian rainfall trends, potential instability of the West Antarctic Ice Sheet and changes to the global overturning circulation will be quantified. Understanding these impacts will help to manage Australia's water resources and to predict the future Southern Ocean circulation.Read moreRead less
Sensitivity and Change in the Global Ocean Overturning. The dynamics of the global, deep overturning circulation in the oceans and the way this adjusts to increasing greenhouse forcing will be examined in order to improve our conceptual knowledge of the oceans and the accuracy of climate models. By understanding how the ocean responds to changing surface heat and freshwater fluxes, and particularly the global role of rapid changes in high-latitude seas, we aim to help refine estimates of climate ....Sensitivity and Change in the Global Ocean Overturning. The dynamics of the global, deep overturning circulation in the oceans and the way this adjusts to increasing greenhouse forcing will be examined in order to improve our conceptual knowledge of the oceans and the accuracy of climate models. By understanding how the ocean responds to changing surface heat and freshwater fluxes, and particularly the global role of rapid changes in high-latitude seas, we aim to help refine estimates of climate response times and the warming expected for a given increase in atmospheric greenhouse gases. These two important characteristics of the climate system underlie climate change policy decisions.Read moreRead less
Nonhydrostatic waves and instabilities in rotating fluids. This project addresses a fundamental gap in our understanding of the ocean circulation. The benefits of the program will be to improve the way we model and predict the ocean circulation and the response of the ocean to climate change. The project will thereby assist National Research Priorities on global change and link with a major new ANU Marine Science Strategic Initiative.