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CCRC personnel aim to better understand atmospheric processes, dynamics and thermodynamics. One reason is to reveal the behaviour of a fascinating and important component of the planet, about which many things remain surprisingly mysterious. The work also helps to develop better models for weather and climate prediction, of clear importance for agriculture, power, and other industries like water management, aviation, tourism and of course the general public. Achieving a fundamental understanding based on sound mathematical and physical principles has become ever more pressing in light of climate change, which will cause future weather and climate patterns to be different from past ones, making it harder to get by on empirical "rules of thumb."

Our investigations range from questions of global importance to particular issues affecting Australia. Projects ongoing at the CCRC vary, but an area of current focus is the factors that control Australian rainfall and drought. This includes study of the physics of storms, convection, and clouds and how they interact with climate; atmosphere-ocean dynamics and teleconnections to regional rainfall variability and change associated with climate patterns like El-Nino, and regional modelling of the Australian climate system. We also study changes in atmospheric extremes such as extreme heat and heavy precipitation events, and investigate theories to explain these changes.

CCRC academic staff currently active in this area of research

• Prof. Steve Sherwood
• Prof. Lisa Alexander
• Prof. Jason Evans
• A/Prof. Andrea Taschetto
• Dr Martin Jucker
• Professor Jeremy Bailey (School of Physics, UNSW)

The dependence on fossil fuel energy sources since the industrial revolution has undoubtedly shaped economic prosperity for the developed world. However, an unfortunate by-product of fossil fuel combustion is the emission of carbon dioxide (CO2), an important greenhouse gas that is known to influence long-term climatic variations through its ability to absorb infra-red radiation.

Human emissions of CO2 have resulted in atmospheric levels higher than any period over the last 20 million years. The continued emission of CO2 will lead to widespread climate change related impacts.

Researchers within the Climate Policy and Carbon Cycle sub-program aim to quantify and understand both the human sources and natural sources and sinks of carbon dioxide with the goal to examine international policies required to bring about mitigation of future climate change.

Direct oceanic effects of elevated atmospheric CO2 and biogeochemistry (for example, ocean acidification or coral reef calcification) are also examined through the use of both observations and mathematical modelling techniques.

Another major focus is on how the terrestrial carbon cycle responds to rising atmospheric CO2 and climate change. In particular, the work focuses on the capacity for increasing atmospheric CO2 to stimulate photosynthesis and, in turn, the rate of future climate warming.

Researchers at the CCRC also study climate-carbon cycle interactions on millennial timescales. A particular emphasis is made on past changes in ocean circulation and their impact on the marine carbon cycle and atmospheric CO2.

CCRC staff currently active in this area of research

• A/Prof. Laurie Menviel
• Prof. Katrin Meissner

CCRC research focuses on the nature of climate states in the past, present, and future.

Using coupled climate models in combination with observations data, CCRC is investigating the factors that influence global and regional climate variability on time-scales of days, seasons and centuries.

This work encompasses many diverse aspects of the physical climate system.  A few focus areas are:

• The extratropical and high latitude climate system, including coupled modes of ocean-land-atmosphere variability in the southern hemisphere.
  
• The El Nino - Southern Oscillation and related phenomena in the Tropics, and their impacts on regional climate.
• Temperature and rainfall variability and extremes, and how these are affected by land processes on regional scales.
• Atmospheric dynamics on scales from kilometres to global and its interactions with tropical convection, clouds, the land and the oceans.
• Modelling of climates in Earth's geologic past and their lessons for today.
• The present and future impact of global warming and carbon dioxide/ocean acidification on life in the oceans and on land.

This list is not exhaustive and new topics are always emerging, so please consult the web pages of CCRC staff for more information!

CCRC academic and research staff currently active in this area of research

All staff

This research is focused on the physical changes caused by a changing climate that present diverse risks and hazards for ecosystems and society. The CCRC uses its expertise in climate modelling and climate extremes - in addition to leveraging expertise across epidemiology, risk management, water and food security - to undertake this multidisciplinary research.

Health impacts

The CCRC undertakes research that connects our changing climate to human health impacts. Specifically, we have research projects that integrate weather and climate research with urban systems, urban heat islands, air pollution, socio-economic disadvantage, emergency management responses to heat extremes and public health heat indices.

Indigenous knowledge and impacts

Many Indigenous communities in remote areas of Australia show features of social and economic disadvantage due to inadequate infrastructure, health services and employment. Existing social disadvantage reduces coping ability and may restrict adaptive capacity, affecting these communities’ resilience to climate hazards. Many of these communities strongly connect the health of their ‘Country’ to their cultural, mental and physical well-being.

There is recent recognition of the untapped resource of Indigenous knowledge about past climate change, which could be used to inform adaptation options. However, the oral tradition of recording this knowledge has, until recently, largely hindered non-Indigenous scientists from using this expertise to inform their science. The CCRC works with Indigenous communities to incorporate their knowledge of past climate changes and to consider particular impacts of climate change on them.

Agricultural impacts

Future changes in temperature and rainfall, as well as increases in the concentration of carbon dioxide in the atmosphere, have the potential to influence the growth of many important crops in complex ways. The CCRC supports work done by the NSW Department of Primary Industries in modelling these effects.

CCRC academic staff currently active in this area of research

• Prof. Lisa Alexander
• Prof. Andy Pitman
• Prof. Jason Evans

Climate models form the basis of future climate projections. They embody what we know about how the Earth system works.

A critical component of building trust in climate models is testing them against observations of past climate - model evaluation.

CCRC researchers are actively involved in both the collation and synthesis of observational data for model evaluation and the development of model evaluation techniques that help us understand in which circumstances model results are meaningful. This includes:

• Assessing models' ability to reproduce extreme event statistics.
• Assessing the realism of key atmosphere and ocean model processes and their impacts on simulated climate changes.
• Assessing models ability to reproduce observed atmospheric teleconnections, ocean circulation and climate dynamics.
• Assessing and accounting for model dependence with ensemble-based projections.
• Assessing the added value of modelling with higher spatial and temporal resolutions.
• Understanding model sensitivities to land use representation and its effect on local and regional climates.
• International standardisation of model evaluation and benchmarking within the land surface modelling community.

CCRC academic staff currently active in this area of research

• A/Prof. Gab Abramowitz
• Prof. Lisa Alexander
• Prof. Jason Evans
• Prof. Andy Pitman
• A/Prof. Alex Sen Gupta
• Prof. Steven Sherwood
• Prof. Katrin Meissner
• A/Prof. Andréa Taschetto

CCRC research staff currently active in this area of research

• Dr Anna Ukkola

Researchers in the CCRC are currently:

• Investigating the ability of land surface models to reproduce ecosystem carbon and water dynamics. Researchers are working closely with ecosystem-scale land-based observation teams both within Australia and internationally to integrate new streams of ecological data into land surface model parameterisation, benchmarking and evaluation. Specific areas of model development include groundwater-transpration relationships, representation of heterotrophic respiration and holistic evaluation of water and carbon fluxes in a range of diverse ecosystems globally.
• Development of marine ecosystem models to improve the representation of the marine carbon cycle in climate models.
• Modelling and investigating marine ecosystems in order to better understand their likely impacts and responses to elevated CO2 concentrations and ocean acidification.
• Investigation of the past, present and future ocean carbon cycle and ecosystem-climate related feedbacks.

CCRC academic staff currently active in this area of research

• A/Prof. Gab Abramowitz
• Prof. Katrin Meissner
• Prof. Andy Pitman

CCRC research staff currently active in this area of research

• Dr Anna Ukkola

CCRC undertakes extensive research in ocean sciences with a particular focus on the key ocean processes that affect the climate system. This includes processes such as the El Nino/Southern Oscillation (ENSO), the Indian Ocean Dipole, and Southern Ocean circulation. The CCRC combines world-class ocean modelling, ocean process studies, ocean theory and data synthesis to advance our knowledge of the physics of the oceans.

Areas of focus include the global ocean thermohaline circulation, water-mass formation, the Antarctic Circumpolar Current, western boundary currents, ocean meso-scale eddies and the ocean carbon and nutrients cycles.

The oceanography group combines regional and global scale models with observations data to investigate ocean dynamics. A core research focus is the role of the oceans in climatic processes, particularly at mid-to high-latitudes and in the Indian and Pacific Oceans.

Significant research effort is also invested in paleoceanography, the role of ocean gateways in climate, coupled ocean-carbon-atmosphere feedbacks, and the transport of heat and freshwater by the oceans.

CCRC academic staff currently active in this area of research

• A/Prof. Alex Sen Gupta
• Prof. Katrin Meissner
• A/Prof. Laurie Menviel
• A/Prof. Andréa Taschetto

CCRC research staff currently active in this area of research

• Dr Leela Frankcombe

A key problem for reducing the uncertainty in climate projections is historical records of change are often too short to test the skill of climate models, raising concerns over our ability to successfully plan for future change. Published records only allow a robust reconstruction of global temperature back to around 1850 and show a ‘gradual’ warming trend of around 0.8°C. However, a wealth of geological, chemical, and biological records clearly indicate large changes in the climate system took place in the past. The forcing associated with these changes appear to have been relatively small, implying the associated thresholds (often described as ‘tipping points’) are considerably smaller than generally supposed. Gradual variations in the global climate on decadal to millennial timescales allow us to study the sensitivity of the climate system to external forcings, improving our estimates of the response to increasing concentrations of atmospheric greenhouse gases.

Against a backdrop of enhanced anthropogenic-driven climate change, it is essential we have a better understanding of the earth-ocean-atmosphere system. The Palaeoclimate Science team in the CCRC is actively researching a number of competing theories and models of annual to millennial-scale change, aiming to better understand the global system. By generating highly precise and accurate climatic changes from around the world, we are working to test the degree to which changes were synchronous (or not) across a range of periods in the geological past, and identify the mechanisms by which the climate signals were propagated globally. These results are critical for improving our ability to reduce future uncertainty.

The principal areas of research include:

• Modelling the Earth system using a range of models with varying degrees of complexity.
• Modelling of climate-carbon cycle interactions on glacial to centennial timescales.
• Investigating the mechanisms, feedbacks and thresholds underlying past abrupt climate events.
• Reconstructing past ice sheet extent and their contribution to global sea level.
• Exploring the role of Southern Hemisphere Westerlies (SHW) on ocean circulation and the carbon cycle.
• Reconstructing different modes of climate, including the Southern Annular Mode (often abbreviated to SAM), the El Niño-Southern Oscillation (ENSO) and the East Asian Monsoon (EAM).
• Terrestrial, ice and marine climate reconstruction for key periods including the last 2000 years, the termination of the last glacial period (Termination 1) and the Last Interglacial (Stage 5e).
• Climate forcing, including volcanic and solar, ocean gateways and their influence on the evolution of the planet’s climate.
• Improved methods for climate reconstruction, chronological control and data-model comparison.

Team members working in palaeoclimate science include:

• Prof. Katrin Meissner
• A/Prof. Laurie Menviel

CCRC undertakes a major program in the parameterisation of terrestrial processes in regional and global climate models. The terrestrial system includes surface hydrology, river flow, soil processes, vegetation processes and snow.

Major challenges yet to be addressed include ground water and permafrost. Our interests include the improvement of existing models by enhancing the representation of biophysical processes. This is achieved using surface observations where possible. New observing systems, especially satellite based sensors, are also used to monitor various aspects of the terrestrial system and to both inform and evaluate our models.

We also explore the impact of terrestrial processes on the simulation of weather and climate. This is not merely the mean climate; we're interested in extremes and predictability. We're also interested in how changes in the nature of the land surface may affect regional and global climate. Issues relating to non-linear responses driven by surface processes on future climate - such as loss of terrestrial carbon due to global warming - are emerging priorities.

CCRC academic staff currently active in this area of research

• Prof. Jason Evans
• A/Prof. Gab Abramowitz
• Prof. Andy Pitman
• Prof. Katrin Meissner

CCRC research staff currently active in this area of research

• Dr Anna Ukkola