ACCESS-S2 seasonal forecasts of rainfall and the SAM–rainfall relationship during the grain growing season in south-west Western Australia DOI Creative Commons
R. H. Firth, Jatin Kala, Debra Hudson

et al.

Journal of Southern Hemisphere Earth System Science, Journal Year: 2024, Volume and Issue: 74(3)

Published: Sept. 3, 2024

South-west Western Australia (SWWA) is home to a world class grains industry that significantly affected by periods of drought. Previous research has shown link between the Southern Annular Mode (SAM) and rainfall in SWWA, especially during winter months. Hence, predictability SAM its relationship SWWA can potentially improve forecasts drought, which would provide valuable information for farmers. In this paper, focusing on 0-month lead time forecast, we assess bias skill ACCESS-S2, Australian Bureau Meteorology’s current operational sub-seasonal seasonal forecasting system, simulating growing season (May–October). We then analyse precipitation how well captured ACCESS-S2 as monthly index. Finally, simulation are assessed case study extreme drought 2010. Our results show tend have greater earlier part (May–July). captures significant inverse SAM–rainfall but underestimates strength. The model also shows overall index MSLP 850-hPa wind anomaly patterns associated with positive negative phases. However, 2010 study, does not indicate strong likelihoods upcoming dry conditions, particularly later season, despite predicting (although weaker than observed) Although skillfully depict SAM–SWWA generally forecast well, still limited skill. Hence it likely errors unrelated contributing low seasonal-timescale region.

Language: Английский

Analysis of the Observed Trends in Rainfall and Temperature Patterns in North-Eastern Nigeria DOI Open Access
Deborah Ishaku, Emmanuel Tanko Umaru,

A.A. Adebayo

et al.

Climate, Journal Year: 2024, Volume and Issue: 12(12), P. 219 - 219

Published: Dec. 11, 2024

The present study offers a comprehensive evaluation of the monthly rainfall and temperature patterns across nine stations fifty-nine points in North-Eastern Nigeria using NASA’s Prediction Worldwide Energy Resources data, spanning four decades (1981–2021). By employing Mann–Kendall (MK) test inverse distance weighting (IDW) interpolation, researchers effectively detected visualized trends climate variables. MK results indicate contrasting trends, with notable decreases Akko, Billiri, Maiduguri, Numan, Yola, increases Gombe, Abadam, Biu, Mubi. maximum were found to be statistically significant all stations, showing consistent increase, whereas minimum exhibited slight but insignificant decrease. application Theil–Sen slope estimator quantified these providing nuanced insights into magnitudes changes IDW further corroborate general trend decreasing (z = −0.442), modest 0.046), marginal decline −0.005). This makes an important contribution by advocating for proactive dissemination information. Given evident shifts, particularly increasing temperatures fluctuating patterns, timely access such information is crucial enhancing resilience region. rigorous statistical methods applied detailed spatial analysis strengthen validity findings, making this valuable resource both policymakers aiming address variability Nigeria. These research may also useful understanding variabilities different parts world.

Language: Английский

Citations

2
A Multiscale Evaluation of the Wet 2022 in Eastern Australia DOI Open Access
Kimberley J. Reid, Michael A. Barnes, Zoe E. Gillett

et al.

Journal of Climate, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 12, 2024

Abstract Eastern Australia experienced record-breaking rainfall and flooding during 2022, which devastated communities led to over AU$6 billion of damage. In this study, we conduct a multiscale analysis understand why 2022 was unusually wet with multiple events the year. We assess synoptic mesoscale conditions three key periods: February-March, July, October. These periods were chosen because they impactful represent different seasons. Next, examine large-scale climate drivers evaluate how unusual these compared previous years. Finally, discuss predictability possible impact change on heavy in eastern Australia. The exceptional likely due excessive slow-moving cyclones combined ample atmospheric moisture flux. (El Niño-Southern Oscillation, Indian Ocean Dipole, Southern Annular Mode) primed for frequent rain-bearing weather systems. There limited beyond one-week lead time February-March July events, but one-month seasonal forecast October indicated complexity multiday extreme makes it difficult distinguish role from natural variability. However, highlight where future research could focus help us risks region. Our results emphasise importance examining perspectives considering interactions between scales analysing isolation is insufficient explaining high weather.

Language: Английский

Citations

2
Subtropical Foehn Winds, Southeast Queensland, Australia DOI Creative Commons

Leon Wiesner,

Hamish A. McGowan, Andrew Sturman

et al.

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(13)

Published: July 2, 2024

Abstract Foehn winds have been a focus of research in mid‐latitude mountainous regions for more than 150 years, where their onset is typically associated with warm, dry, and gusty winds. This has now extended into high latitude regions, yet foehn subtropical tropical remains scarce. Here we present results from the first investigation subtropics Southeast Queensland (SEQ), Australia. Analysis meteorological records found that occur throughout year peak frequency duration late winter (August) passage shortwave troughs over southern Modeling wind fields atmospheric boundary layer conditions three case studies was conducted using Weather Research Forecasting (WRF) model. Results showed events SEQ can be mountain waves hydraulic jump features lee topographic barriers. Over slopes, acceleration speeds channeling to occur, along substantial increases air temperature, decreases relative humidity. Warming airstream believed primarily through isentropic drawdown likely contribution surface sensible heat flux. Recommendations future are made light importance wildfire management mitigation SEQ.

Language: Английский

Citations

1
The role played by the Indian Ocean High in affecting winter precipitation over Victoria, Australia DOI

Saqib Ur Rehman,

Ian Simmonds, Bilal Ahmed Usmani

et al.

Dynamics of Atmospheres and Oceans, Journal Year: 2024, Volume and Issue: 107, P. 101484 - 101484

Published: July 11, 2024

Language: Английский

Citations

1
ACCESS-S2 seasonal forecasts of rainfall and the SAM–rainfall relationship during the grain growing season in south-west Western Australia DOI Creative Commons
R. H. Firth, Jatin Kala, Debra Hudson

et al.

Journal of Southern Hemisphere Earth System Science, Journal Year: 2024, Volume and Issue: 74(3)

Published: Sept. 3, 2024

South-west Western Australia (SWWA) is home to a world class grains industry that significantly affected by periods of drought. Previous research has shown link between the Southern Annular Mode (SAM) and rainfall in SWWA, especially during winter months. Hence, predictability SAM its relationship SWWA can potentially improve forecasts drought, which would provide valuable information for farmers. In this paper, focusing on 0-month lead time forecast, we assess bias skill ACCESS-S2, Australian Bureau Meteorology’s current operational sub-seasonal seasonal forecasting system, simulating growing season (May–October). We then analyse precipitation how well captured ACCESS-S2 as monthly index. Finally, simulation are assessed case study extreme drought 2010. Our results show tend have greater earlier part (May–July). captures significant inverse SAM–rainfall but underestimates strength. The model also shows overall index MSLP 850-hPa wind anomaly patterns associated with positive negative phases. However, 2010 study, does not indicate strong likelihoods upcoming dry conditions, particularly later season, despite predicting (although weaker than observed) Although skillfully depict SAM–SWWA generally forecast well, still limited skill. Hence it likely errors unrelated contributing low seasonal-timescale region.

Language: Английский

Citations

1