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The evolution of industrial-era warming across the continents and oceans provides a context for future climate change and is important for determining climate sensitivity and the processes that control regional warming. Here we use post-ad 1500 palaeoclimate records to show that sustained industrial-era warming of the tropical oceans first developed during the mid-nineteenth century and was nearly synchronous with Northern Hemisphere continental warming. The early onset of sustained, significant warming in palaeoclimate records and model simulations suggests that greenhouse forcing of industrial-era warming commenced as early as the mid-nineteenth century and included an enhanced equatorial ocean response mechanism. The development of Southern Hemisphere warming is delayed in reconstructions, but this apparent delay is not reproduced in climate simulations. Our findings imply that instrumental records are too short to comprehensively assess anthropogenic climate change and that, in some regions, about 180 years of industrial-era warming has already caused surface temperatures to emerge above pre-industrial values, even when taking natural variability into account., Author(s): Nerilie J. Abram (corresponding author) [1, 2]; Helen V. McGregor [3]; Jessica E. Tierney [4, 5]; Michael N. Evans [6]; Nicholas P. McKay [7]; Darrell S. Kaufman [7]; the [...]

Evidence contained within historical documents and inscriptions provides an important record of climate variability for periods prior to the onset of systematic meteorological data collection. A common approach used by historical climatologists to convert such qualitative documentary evidence into continuous quantitative proxy data is through the generation of ordinal-scale climate indices. There is, however, considerable variability in the types of phenomena reconstructed using an index approach and the practice of index development in different parts of the world. This review, written by members of the PAGES CRIAS Working Group -- a collective of climate historians and historical climatologists researching Climate Reconstructions and Impacts from the Archives of Societies -- provides the first global synthesis of the use of the index approach in climate reconstruction. We begin by summarising the range of studies that have used indices for climate reconstruction across six continents (Europe, Asia, Africa, the Americas, Australia) plus the world's oceans. We then outline the different methods by which indices are developed in each of these regions, including a discussion of the processes adopted to verify and calibrate index series, and the measures used to express confidence and uncertainty. We conclude with a series of recommendations to guide the development of future index-based climate reconstructions to maximise their effectiveness for use by climate modellers and in multiproxy climate reconstructions. [ABSTRACT FROM AUTHOR]

El Niño-Southern Oscillation is the major source of interannual rainfall variability in the Australian region, with the strongest influence over eastern Australia. The strength of this regional ENSO-rainfall teleconnection varies in the observational record. Climate model simulations of the 'last millennium' (850-1850 C.E.) can be used to quantify the natural variability of the relationship between ENSO and Australian rainfall on decadal and longer time scales, providing a baseline for evaluating future projections. In this study, historical and last millennium (LM) simulations from six models were obtained from the Coupled Model Intercomparison Project Phase 5 and Palaeoclimate Modelling Intercomparison Project Phase 3. All models reproduce the observed negative correlation between September to February (SONDJF) eastern Australian rainfall and the NINO3.4 index, with varying skill. In the LM simulations, all models produce decadal-scale cooling over eastern Australia in response to volcanic forcing, as well as a long-term cooling trend. Rainfall variability over the same region is not strongly driven by external forcing, with each model simulating rainfall anomalies of different phase and magnitude. SONDJF eastern Australian rainfall is strongly correlated with ENSO in the LM simulations for all models, although some models simulate periods when the teleconnection weakens substantially for several decades. Changes in ENSO variance play a role in modulating the teleconnection strength, but are not the only factor. The long-term average spatial pattern of the ENSO-Australian rainfall teleconnection is similar in the LM and historical simulations, although the spatial pattern varies over time in the LM simulations. [ABSTRACT FROM AUTHOR]

A new index is developed for the Interdecadal Pacific Oscillation, termed the IPO Tripole Index (TPI). The IPO is associated with a distinct 'tripole' pattern of sea surface temperature anomalies (SSTA), with three large centres of action and variations on decadal timescales, evident in the second principal component (PC) of low-pass filtered global SST. The new index is based on the difference between the SSTA averaged over the central equatorial Pacific and the average of the SSTA in the Northwest and Southwest Pacific. The TPI is an easily calculated, non-PC-based index for tracking decadal SST variability associated with the IPO. The TPI time series bears a close resemblance to previously published PC-based indices and has the advantages of being simpler to compute and more consistent with indices used to track the El Niño-Southern Oscillation (ENSO), such as Niño 3.4. The TPI also provides a simple metric in physical units of °C for evaluating decadal and interdecadal variability of SST fields in a straightforward manner, and can be used to evaluate the skill of dynamical decadal prediction systems. Composites of SST and mean sea level pressure anomalies reveal that the IPO has maintained a broadly stable structure across the seven most recent positive and negative epochs that occurred during 1870-2013. The TPI is shown to be a robust and stable representation of the IPO phenomenon in instrumental records, with relatively more variance in decadal than shorter timescales compared to Niño 3.4, due to the explicit inclusion of off-equatorial SST variability associated with the IPO. [ABSTRACT FROM AUTHOR]

Despite the great potential of palaeo-environmental information to strengthen natural resource policy, science and practical outcomes naturally occurring archives of palaeo-environmental and ecosystem service information have not been fully recognised or utilised to inform the development of environmental policy. In this paper, we describe how Australian palaeo-environmental science is improving environmental understanding through local studies and regional syntheses that inform us about past conditions, extreme conditions and altered ecosystem states. Australian innovations in ecosystem services research and palaeo-environmental science contribute in five important contexts: discussions about environmental understanding and management objectives, improving access to information, improved knowledge about the dynamics of ecosystem services, increasing understanding of environmental processes and resource availability, and engaging interdisciplinary approaches to manage ecosystem services. Knowledge of the past is an important starting point for setting present and future resource management objectives, anticipating consequences of trade-offs, sharing risk and evaluating and monitoring the ongoing availability of ecosystem services. Palaeo-environmental information helps reframe discussions about desirable futures and collaborative efforts between scientists, planners, managers and communities. However, further steps are needed to translate the ecosystem services concept into ecosystem services policy and tangible management objectives and actions that are useful, feasible and encompass the range of benefits to people from ecosystems. We argue that increased incorporation of palaeo-environmental information into policy and decision-making is needed for evidence-based adaptive management to enhance sustainability of ecosystem functions and reduce long-term risks. [ABSTRACT FROM PUBLISHER]

The article offers information on the 3rd Aus2k workshop which aims to review progress made by the Aus2k community to date, and to develop specific plans to contribute Australasian science towards Phase 2 of the PAGES 2k Network. The workshop was attended by a number of palaeoclimatologists, meteorologists, hydrologists, and oceanographers. It mentions the participation of the Australian Climate Change Science Program (ACCSP).

The article discusses a workshop on 4TH AUS2K sponsored by the National Institute of Water and Atmospheric Research (NIWA) that was held in Auckland, New Zealand from October 27-29, 2015.