Long-term stationarity of El Niño–Southern Oscillation teleconnections in southeastern Australia

Ashcroft, Linden; Gergis, Joëlle; Karoly, David J.

doi:10.1007/s00382-015-2746-3

Cited by 39 publications

(35 citation statements)

References 70 publications

(146 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This confirms fluctuations in the influence of Pacific Ocean-driven climate variability and temperatures in the Australasian region during the instrumental period (e.g., around 1960) and reduced correlations in the mid-seventeen century. Large variations in the relationship between Australasian temperature and ENSO are consistent with instrumental data and climate model simulations (Gallant et al 2013;Ashcroft et al 2016). Graham et al (2011) present results from a coupled GCM showing that a slight warming of the tropical Indian and western Pacific Oceans relative to the other tropical ocean basins may have induced a broad range of the circulation and climate changes indicated by proxy data in the medieval period, including many of those not explained by a cooler eastern tropical Pacific alone.…”

Section: Ocean-atmosphere Interactionssupporting

confidence: 73%

Australasian Temperature Reconstructions Spanning the Last Millennium

et al. 2016

Self Cite

View full text Add to dashboard Cite

Multiproxy warm season (September-February) temperature reconstructions are presented for the combined land-ocean region of Australasia (0º-50ºS, 110ºE-180º) covering . Using between 2 (R2) and 28 (R28) paleoclimate records, four 1000-member ensemble reconstructions of regional temperature are developed using four statistical methods: principal component regression (PCR), composite plus scale (CPS), Bayesian hierarchical models (LNA), and pairwise comparison (PaiCo). The reconstructions are then compared with a three-member ensemble of GISS-E2-R climate model simulations and independent paleoclimate records. Decadal fluctuations in Australasian temperatures are remarkably similar between the four reconstruction methods. There are, however, differences in the amplitude of temperature variations between the different statistical methods and proxy networks. When the R28 network is used, the warmest 30-yr periods occur after 1950 in 77% of ensemble members over all methods. However, reconstructions based on only the longest records (R2 and R3 networks) indicate that single 30-and 10-yr periods of similar or slightly higher temperatures than in the late twentieth century may have occurred during the first half of the millennium. Regardless, the most recent instrumental temperatures are above the 90th percentile of all 12 reconstruction ensembles (four reconstruction methods based on three proxy networks-R28, R3, and R2). The reconstructed twentieth-century warming cannot be explained by natural variability alone using GISS-E2-R. In this climate model, anthropogenic forcing is required to produce the rate and magnitude of post-1950 warming observed in the Australasian region. These paleoclimate results are consistent with other studies that attribute the post-1950 warming in Australian temperature records to increases in atmospheric greenhouse gas concentrations. ABSTRACTMultiproxy warm season (September-February) temperature reconstructions are presented for the combined land-ocean region of Australasia (08-508S, 1108E-1808) covering 1000-2001. Using between 2 (R2) and 28 (R28) paleoclimate records, four 1000-member ensemble reconstructions of regional temperature are developed using four statistical methods: principal component regression (PCR), composite plus scale (CPS), Bayesian hierarchical models (LNA), and pairwise comparison (PaiCo). The reconstructions are then compared with a three-member ensemble of GISS-E2-R climate model simulations and independent paleoclimate records. Decadal fluctuations in Australasian temperatures are remarkably similar between the four reconstruction methods. There are, however, differences in the amplitude of temperature variations between the different statistical methods and proxy networks. When the R28 network is used, the warmest 30-yr periods occur after 1950 in 77% of ensemble members over all methods. However, reconstructions based on only the longest records (R2 and R3 networks) indicate that single 30-and 10-yr periods of similar or slightly higher temperature...

show abstract

Section: Ocean-atmosphere Interactionssupporting

confidence: 73%

Australasian Temperature Reconstructions Spanning the Last Millennium

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…Eastern and Southern Australia, North-Eastern South America, India, and Southern Africa (Ashcroft et al, 2016;Davey et al, 2014).…”

Section: Geophysical Research Lettersmentioning

confidence: 99%

Global Changes in Drought Conditions Under Different Levels of Warming

Naumann

Alfieri

Wyser

et al. 2018

Geophysical Research Letters

571

298

View full text Add to dashboard Cite

Higher evaporative demands and more frequent and persistent dry spells associated with rising temperatures suggest that drought conditions could worsen in many regions of the world. In this study, we assess how drought conditions may develop across the globe for 1.5, 2, and 3°C warming compared to preindustrial temperatures. Results show that two thirds of global population will experience a progressive increase in drought conditions with warming. For drying areas, drought durations are projected to rise at rapidly increasing rates with warming, averaged globally from 2.0 month/°C below 1.5°C to 4.2 month/°C when approaching 3°C. Drought magnitudes could double for 30% of global landmass under stringent mitigation. If contemporary warming rates continue, water supply‐demand deficits could become fivefold in size for most of Africa, Australia, southern Europe, southern and central states of the United States, Central America, the Caribbean, north‐west China, and parts of Southern America. In approximately 20% of the global land surface, drought magnitude will halve with warming of 1.5°C and higher levels, mainly most land areas north of latitude 55°N, but also parts of South America and Eastern and South‐eastern Asia. A progressive and significant increase in frequency of droughts is projected with warming in the Mediterranean basin, most of Africa, West and Southern Asia, Central America, and Oceania, where droughts are projected to happen 5 to 10 times more frequent even under ambitious mitigation targets and current 100‐year events could occur every two to five years under 3°C of warming.

show abstract

“…Recent efforts to compile and screen early instrumental and historical records have resulted in several papers exploring Southeast Australia's (SEA) hydroclimate and climate teleconnections (e.g. Ashcroft et al 2013Ashcroft et al , 2014Ashcroft et al , 2015. These studies all present caveats about interpretations based on the early historical data due to their geographical bias and reliability issues.…”

Section: Regional Driver(s) Of Hydroclimatementioning

confidence: 99%

Drought variability in the eastern Australia and New Zealand summer drought atlas (ANZDA, CE 1500–2012) modulated by the Interdecadal Pacific Oscillation

Palmer

Cook

Turney

et al. 2015

Environ. Res. Lett.

150

161

View full text Add to dashboard Cite

Agricultural production across eastern Australia and New Zealand is highly vulnerable to drought, but there is a dearth of observational drought information prior to CE 1850. Using a comprehensive network of 176 drought-sensitive tree-ring chronologies and one coral series, we report the first Southern Hemisphere gridded drought atlas extending back to CE 1500. The austral summer (December-February) Palmer drought sensitivity index reconstruction accurately reproduces historically documented drought events associated with the first European settlement of Australia in CE 1788, and the leading principal component explains over 50% of the underlying variance. This leading mode of variability is strongly related to the Interdecadal Pacific Oscillation tripole index (IPO), with a strong and robust antiphase correlation between (1) eastern Australia and the New Zealand North Island and (2) the South Island. Reported positive, negative, and neutral phases of the IPO are consistently reconstructed by the drought atlas although the relationship since CE 1976 appears to have weakened.

show abstract

Long-term stationarity of El Niño–Southern Oscillation teleconnections in southeastern Australia

Cited by 39 publications

References 70 publications

Australasian Temperature Reconstructions Spanning the Last Millennium

Australasian Temperature Reconstructions Spanning the Last Millennium

Global Changes in Drought Conditions Under Different Levels of Warming

Drought variability in the eastern Australia and New Zealand summer drought atlas (ANZDA, CE 1500–2012) modulated by the Interdecadal Pacific Oscillation

Contact Info

Product

Resources

About