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As more countries make net zero greenhouse gas emissions pledges, it is crucial to understand the effects on global climate after achieving net zero emissions. The climate has been found to continue to evolve even after the abrupt cessation of CO2 emissions, with some models simulating a small warming and others simulating a small cooling. In this study, we analyze if the temperature and precipitation changes post abrupt cessation of CO2 emissions are significantly different compared to natural climate variations. We find that the temperature changes are outside of natural variability for most models, whilst the precipitation changes are mostly non‐significant. We also demonstrate that post‐net zero temperature changes have implications for the remaining carbon budget. The possibility of further global warming post‐net zero adds to the evidence supporting more rapid emissions reductions in the near‐term. Plain Language Summary: As more countries commit to achieving net‐zero greenhouse gas emissions, it is essential to understand the impact this will have on the global climate beyond this point. It has been found that even after CO2 emissions are abruptly halted, the climate continues to change, with various models predicting either a slight warming or cooling effect. In our study, we investigate whether the temperature and precipitation changes that occur after the sudden cessation of CO2 emissions are noteworthy when compared to natural climate variations. Our analysis reveals that the temperature changes, in the majority of models, surpass what can be attributed to natural variability. However, the precipitation changes are generally not significant. Additionally, we observe that the temperature changes post‐net zero have implications for the remaining carbon budget. Key Points: Global mean surface temperature changes after abrupt CO2 emissions cessation are significant compared to natural variability in most modelsGlobal mean precipitation changes after 50 yrs are only significant compared to natural variability in models that warmThe uncertain temperature changes post‐net zero have implications for the remaining carbon budget [ABSTRACT FROM AUTHOR]

Nodular melanoma (NM) is the third most common subtype of melanoma among African Americans trailing behind acral lentiginous melanoma and superficial spreading melanoma. This case of NM in an African American Japanese male was selected due to the rare occurrence of NM in people of color. [ABSTRACT FROM AUTHOR]

Studies of atmospheric rivers (ARs) over Australia have, so far, only focused on northwest cloudband–type weather systems. Here we perform a comprehensive analysis of AR climatology and impacts over Australia that includes not only northwesterly systems, but easterly and extratropical ARs also. We quantify the impact of ARs on mean and extreme rainfall including assessing how the origin location of ARs can alter their precipitation outcomes. We found a strong relationship between ARs and extreme rainfall in the agriculturally significant Murray–Daring basin region. We test the hypothesis that the tropical and subtropical originating ARs we observe in Australasia differ from canonical extratropical ARs by examining the vertical structure of ARs grouped by origin location. We found that in the moisture abundant tropics and subtropics, wind speed drives the intensity of ARs, while in the extratropics, the strength of an AR is largely determined by moisture availability. Finally, we examine the modulation of AR frequency by different climate modes. We find weak (but occasionally significant) correlations between ARs frequency and El Niño–Southern Oscillation, the Indian Ocean dipole, and the southern annular mode. However, there is a stronger relationship between the phases of the Madden–Julian oscillation and tropical AR frequency, which is an avenue for potential skill in forecasting ARs on subseasonal time scales. [ABSTRACT FROM AUTHOR]

Successful treatment of cabozantinib-induced pyoderma gangrenosum with ixekizumab therapy: A case report Pyoderma gangrenosum (PG) is a painful dermatosis characterized by neutrophilic infiltration and ulcer with rapid progression. At the end of a 12-week treatment period, the second ulcer was in full resolution and the initial ulcer showed significant diminution in size (Figure 1D). [Extracted from the article]

Artificial spin ices are frustrated spin systems that can be engineered, in which fine tuning of geometry and topology has allowed the design and characterization of exotic emergent phenomena at the constituent level. Here, we report a realization of spin ice in a lattice of superconducting qubits. Unlike conventional artificial spin ice, our system is disordered by both quantum and thermal fluctuations. The ground state is classically described by the ice rule, and we achieved control over a fragile degeneracy point, leading to a Coulomb phase. The ability to pin individual spins allows us to demonstrate GaussÕs law for emergent effective monopoles in two dimensions. The demonstrated qubit control lays the groundwork for potential future study of topologically protected artificial quantum spin liquids. [ABSTRACT FROM AUTHOR]

Seasonal climate prediction to date has largely focussed on probabilistic forecasts for above‐ and below‐average conditions in climate means. Here, we examine the possibility of making sub‐seasonal to seasonal outlooks for daily‐scale precipitation extremes in Australia. We first use observational data to show that significant relationships exist between climate modes, such as the El Niño–Southern Oscillation, and indices representing rainfall extremes across much of Australia. The strong observed teleconnections between climate modes and daily rainfall extremes suggest the potential for predictability on seasonal scales. The current Australian Bureau of Meteorology seasonal prediction system (ACCESS‐S1) is examined for performance in predicting rainfall extreme indices using a range of measures. Ensemble hindcasts, consisting of 11 members initialised every month during 1990–2012, perform well for some extreme rainfall indices on short lead‐times (up to 1 month). We note that at short lead‐times, forecasts are aided by skilful weather prediction, so forecast performance drops at lead‐times of a week or more. Forecast performance is lower in austral summer than other seasons and greater in the north and interior of the continent, particularly in the dry season, than elsewhere. The ACCESS‐S1 ensemble is overconfident but exhibits some reliability in probabilistic forecasts of above‐ or below‐average number of wet days and intensity of the highest daily maximum precipitation, especially in northern Australia. ACCESS‐S1 captures the broad pattern of relationships between climate modes and rainfall extremes that are observed. For two case‐studies of unusually extreme precipitation, ACCESS‐S exhibits contrasting performance for forecasts of extreme rainfall anomalies beyond the first month. These results suggest that ACCESS‐S1 may be used to produce outlooks for some rainfall indices, such as the number of wet days and the intensity of the wettest day, for the month ahead. [ABSTRACT FROM AUTHOR]

Extended warning of above‐average and extreme precipitation is valuable to a wide range of stakeholders. However, the sporadic nature of precipitation makes it difficult to forecast skilfully beyond one week. Subseasonal forecasting is a growing area of science that aims to predict average weather conditions multiple weeks in advance using dynamical models. Building on recent work in this area, we test the hypothesis that using large‐scale horizontal moisture transport as a predictor for precipitation may increase the forecast skill of the above‐median and high‐precipitation weeks on subseasonal time‐scales. We analysed retrospective forecast (hindcast) sets from the Australian Bureau of Meteorology's latest operational subseasonal‐to‐seasonal forecasting model, ACCESS‐S2, to compare the forecast skill of precipitation using integrated water vapour transport (IVT) as a proxy, compared to using precipitation forecasts directly. We show that ACCESS‐S2 precipitation generally produces more skilful forecasts, except over some regions where IVT could be a useful additional diagnostic for warning of heavy precipitation events. [ABSTRACT FROM AUTHOR]

Given the Paris Agreement it is imperative there is greater understanding of the consequences of limiting global warming to the target 1.5° and 2°C levels above preindustrial conditions. It is challenging to quantify changes across a small increment of global warming, so a pattern-scaling approach may be considered. Here we investigate the validity of such an approach by comprehensively examining how well local temperatures and warming trends in a 1.5°C world predict local temperatures at global warming of 2°C. Ensembles of transient coupled climate simulations from multiple models under different scenarios were compared and individual model responses were analyzed. For many places, the multimodel forced response of seasonalaverage temperatures is approximately linear with global warming between 1.5° and 2°C. However, individual model results vary and large contributions from nonlinear changes in unforced variability or the forced response cannot be ruled out. In some regions, such as East Asia, models simulate substantially greater warming than is expected from linear scaling. Examining East Asia during boreal summer, we find that increased warming in the simulated 2°C world relative to scaling up from 1.5°C is related to reduced anthropogenic aerosol emissions. Our findings suggest that, where forcings other than those due to greenhouse gas emissions change, the warming experienced in a 1.5°C world is a poor predictor for local climate at 2°C of global warming. In addition to the analysis of the linearity in the forced climate change signal, we find that natural variability remains a substantial contribution to uncertainty at these low-warming targets. [ABSTRACT FROM AUTHOR]

Abstract: The Paris Agreement aims to keep global warming well below 2°C above preindustrial levels with a preferred ambitious 1.5°C target. Developing countries, especially small island nations, pressed for the 1.5°C target to be adopted, but who will suffer the largest changes in climate if we miss this target? Here we show that exceeding the 1.5°C global warming target would lead to the poorest experiencing the greatest local climate changes. Under these circumstances greater support for climate adaptation to prevent poverty growth would be required. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examines the roles of both human-induced climate change and natural climate variability in the record wet winter southeast Australia. Information about the influence of the two factors on the circulation patterns conducive to unusually wet seasons as well as moisture availability is presented.

Record-breaking temperatures can detrimentally impact ecosystems, infrastructure, and human health. Previous studies show that climate change has influenced some observed extremes, which are expected to become more frequent under enhanced future warming. Understanding the magnitude, as a well as frequency, of such future extremes is critical for limiting detrimental impacts. We focus on temperature changes in Australian regions, including over a major coral reef-building area, and assess the potential magnitude of future extreme temperatures under Paris Agreement global warming targets (1.5°C and 2°C). Under these limits to global mean warming, we determine a set of projected high-magnitude unprecedented Australian temperature extremes. These include extremes unexpected based on observational temperatures, including current record-breaking events. For example, while the difference in global-average warming during the hottest Australian summer and the 2°C Paris target is 1.1°C, extremes of 2.4°C above the observed summer record are simulated. This example represents a more than doubling of the magnitude of extremes, compared with global mean change, and such temperatures are unexpected based on the observed record alone. Projected extremes do not necessarily scale linearly with mean global warming, and this effect demonstrates the significant potential benefits of limiting warming to 1.5°C, compared to 2°C or warmer. [ABSTRACT FROM AUTHOR]

The article focuses on defining new normal for extreme weather in climate change. A new normal has been applied to describe a diversity of weather and climate phenomena. Directing analysis of a new normal to extreme temperatures is motivated by several factors. Extreme weather and climate events occurring on subdaily to multiyear time scales and have significant socioeconomic costs and impacts on natural systems.

A graph is strongly even-cycle decomposable if the edge set of every subdivision with an even number of edges can be partitioned into cycles of even length. We prove that several fundamental composition operations that preserve the property of being Eulerian also yield strongly even-cycle decomposable graphs. As an easy application of our theorems, we give an exact characterization of the set of strongly even-cycle decomposable cographs. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the role of El Niño and human-induced climate change to the increase in likelihood of heat and drought in Indonesia in July-October 2015. The study used the temperature and precipitation to assess the extreme event in the country. Results show that the dry season was attributed to El Niño and climate change.

In 1998 the second author proved that there is an ε > 0 such that every graph satisfies ≤ [(1 - ε)(Δ+ 1) + εω]. The first author recently proved that any graph satisfying ω > 23 (Δ + 1) contains a stable set intersecting every maximum clique. In this note, we exploit the latter result to give a much shorter, simpler proof of the former. Working from first principles, we omit only some five pages of proofs of known intermediate results (which appear in an extended version of this paper), and the proofs of Hall's Theorem, Brooks' Theorem, the Lovász Local Lemma, and Talagrand's Inequality. [ABSTRACT FROM AUTHOR]

The article examines the possible reasons behind the heat event in Brisbane, Queelands during the G20 Summit in November 2014. Topics covered include daytime maximum temperatures, the influence of human-induced climate change on the odds of abnormally hot says in Brisband in the month of November and the conclusion that anthropogenic climate change has increased the odds of hot and very hot days.

The second author's (B.A.R.) ω, Δ, χ conjecture proposes that every graph satisfies [ABSTRACT FROM AUTHOR]

The article discusses the influence of human activity and extreme drought on the record heat experienced across inland eastern Australia in 2013. Topics discussed include the probability that human-induced climate change increased the risk of hot and dry years in the country and the effect of the lack of precipitation during the year to the extreme weather condition. Also mentioned are model simulations and the dataset used in the study.

Leading patterns of observed monthly extreme rainfall variability in Australia are examined using an empirical orthogonal teleconnection (EOT) method. Extreme rainfall variability is more closely related to mean rainfall variability during austral summer than in winter. The leading EOT patterns of extreme rainfall explain less variance in Australia-wide extreme rainfall than is the case for mean rainfall EOTs. The authors illustrate that, as with mean rainfall, the El Niño-Southern Oscillation (ENSO) has the strongest association with warm-season extreme rainfall variability, while in the cool season the primary drivers are atmospheric blocking and the subtropical ridge. The Indian Ocean dipole and southern annular mode also have significant relationships with patterns of variability during austral winter and spring. Leading patterns of summer extreme rainfall variability have predictability several months ahead from Pacific sea surface temperatures (SSTs) and as much as a year in advance from Indian Ocean SSTs. Predictability from the Pacific is greater for wetter-than-average summer months than for months that are drier than average, whereas for the Indian Ocean the relationship has greater linearity. Several cool-season EOTs are associated with midlatitude synoptic-scale patterns along the south and east coasts. These patterns have common atmospheric signatures denoting moist onshore flow and strong cyclonic anomalies often to the north of a blocking anticyclone. Tropical cyclone activity is observed to have significant relationships with some warm-season EOTs. This analysis shows that extreme rainfall variability in Australia can be related to remote drivers and local synoptic-scale patterns throughout the year. [ABSTRACT FROM AUTHOR]

In every Intergovernmental Panel on Climate Change (IPCC) Assessment cycle, a multitude of scenarios are assessed, with different scope and emphasis throughout the various Working Group reports and special reports, as well as their respective chapters. Within the reports, the ambition is to integrate knowledge on possible climate futures across the Working Groups and scientific research domains based on a small set of "framing pathways" such as the so-called representative concentration pathways (RCPs) in the Fifth IPCC Assessment Report (AR5) and the shared socioeconomic pathway (SSP) scenarios in the Sixth Assessment Report (AR6). This perspective, initiated by discussions at the IPCC Bangkok workshop in April 2023 on the "Use of Scenarios in AR6 and Subsequent Assessments", is intended to serve as one of the community contributions to highlight the needs for the next generation of framing pathways that is being advanced under the Coupled Model Intercomparison Project (CMIP) umbrella, which will influence or even predicate the IPCC AR7 consideration of framing pathways. Here we suggest several policy research objectives that such a set of framing pathways should ideally fulfil, including mitigation needs for meeting the Paris Agreement objectives, the risks associated with carbon removal strategies, the consequences of delay in enacting that mitigation, guidance for adaptation needs, loss and damage, and for achieving mitigation in the wider context of societal development goals. Based on this context, we suggest that the next generation of climate scenarios for Earth system models should evolve towards representative emission pathways (REPs) and suggest key categories for such pathways. These framing pathways should address the most critical mitigation policy and adaptation plans that need to be implemented over the next 10 years. In our view, the most important categories are those relevant in the context of the Paris Agreement long-term goal, specifically an immediate action (low overshoot) 1.5 °C pathway and a delayed action (high overshoot) 1.5 °C pathway. Two other key categories are a pathway category approximately in line with current (as expressed by 2023) near- and long-term policy objectives, as well as a higher-emission category that is approximately in line with "current policies" (as expressed by 2023). We also argue for the scientific and policy relevance in exploring two "worlds that could have been". One of these categories has high-emission trajectories well above what is implied by current policies and the other has very-low-emission trajectories which assume that global mitigation action in line with limiting warming to 1.5 °C without overshoot had begun in 2015. Finally, we note that the timely provision of new scientific information on pathways is critical to inform the development and implementation of climate policy. Under the Paris Agreement, for the second global stocktake, which will occur in 2028, and to inform subsequent development of nationally determined contributions (NDCs) up to 2040, scientific inputs are required by 2027. These needs should be carefully considered in the development timeline of community modelling activities, including those under CMIP7. [ABSTRACT FROM AUTHOR]

Abstract: Consider an undirected graph and a subgraph of , on the same vertex set. The -backbone chromatic number is the minimum such that can be properly coloured with colours from , and moreover for each edge of , the colours of its ends differ by at least . In this paper we focus on the case when is planar and is a forest. We give a series of NP-hardness results as well as upper bounds for , depending on the type of the forest (matching, galaxy, spanning tree). Eventually, we discuss a circular version of the problem. [Copyright &y& Elsevier]

A natural generalization of graph colouring involves taking colours from a metric space and insisting that the end-points of an edge receive colours separated by a minimum distance dictated by properties of the edge. In the q-backbone colouring problem, these minimum distances are either q or 1, depending on whether or not the edge is in the backbone. In this paper we consider the list version of this problem, with particular focus on colours in Zp - this problem is closely related to the problem of circular choosability. We first prove that the list circular q-backbone chromatic number of a graph is bounded by a function of the list chromatic number. We then consider the more general problem in which each edge is assigned an individual distance between its endpoints, and provide bounds using the Combinatorial Nullstellensatz. Through this result and through structural approaches, we achieve good bounds when both the graph and the backbone belong to restricted families of graphs. [ABSTRACT FROM AUTHOR]

Abstract: A lemma of Fouquet implies that a claw-free graph contains an induced , contains no odd hole, or is quasi-line. In this paper, we use this result to give an improved shortest-odd-hole algorithm for claw-free graphs by exploiting the structural relationship between line graphs and quasi-line graphs suggested by Chudnovsky and Seymour’s structure theorem for quasi-line graphs. Our approach involves reducing the problem to that of finding a shortest odd cycle of length in a graph. Our algorithm runs in time, improving upon Shrem, Stern, and Golumbic’s recent algorithm, which uses a local approach. The best known recognition algorithms for claw-free graphs run in time, or without fast matrix multiplication. [Copyright &y& Elsevier]

The article discusses whether anthropogenic effects on the climate have affected the relationship between the El Niño-Southern Oscillation (ENSO) and extreme rainfall in southeastern Australia in 2011 to 2012. Figures show that total and extreme rainfall were above average in the austral warm seasons across the region. The greater effect of the magnitude of anomalously cool sea surface temperatures (SST) is also compared to the magnitude of anomalously warm SSTs.

A 0.05° × 0.05° gridded dataset of daily observed rainfall is compared with high-quality station data at 119 sites across Australia for performance in capturing extreme rainfall characteristics. A range of statistics was calculated and analysed for a selection of extreme indices representing the frequency and intensity of heavy rainfall events, and their contribution to total rainfall. As is often found for interpolated data, we show that the gridded dataset tends to underestimate the intensity of extreme heavy rainfall events and the contribution of these events to total annual rainfall as well as overestimating the frequency and intensity of very low rainfall events. The interpolated dataset captures the interannual variability in extreme indices. The spatial extent of significant trends in the frequency of extreme rainfall events is also reproduced to some degree. An investigation into the performance of this gridded dataset in remote areas reveals issues, such as the appearance of spurious trends, when stations come in and out of use. We recommend masking over areas of low station density for this particular gridded data. It is likely that in areas of low station density, gridded datasets will, in general, not perform as well. Therefore, caution should be exercised when examining trends and variability in these regions. We conclude that this gridded product is suitable for use in studies on trends and variability in rainfall extremes across much of Australia. The methodology employed in this study, to examine extreme rainfall over Australia in a gridded dataset, may be applied to other areas of the world. While our study indicates that, in general, gridded datasets can be used to investigate extreme rainfall trends and variability, the data should first be subjected to tests similar to those employed here. [ABSTRACT FROM AUTHOR]

As proved by Kahn, the chromatic number and fractional chromatic number of a line graph agree asymptotically.That is, for any line graph G, we have [ABSTRACT FROM AUTHOR]

King, Lu, and Peng recently proved that for Δ ≥ 4, any KΔ-free graph with maximum degree Δ has fractional chromatic number at most Δ - 2/67 unless it is isomorphic to C5 ... K2 or C8². Using a different approach we give improved bounds for Δ ≥ 6 and pose several related conjectures. Our proof relies on a weighted local generalization of the fractional relaxation of Reed's ω, Δ, χ conjecture. [ABSTRACT FROM AUTHOR]

Reed's w, Δ, χ conjecture proposes that every graph satisfies χ ≤ [1/2(Δ + 1 + w)] it is known to hold for all claw-free graphs. In this paper we consider a local strengthening of this conjecture. We prove the local strengthening for line graphs, then note that previous results immediately tell us that the local strengthening holds for all quasi-line graphs. Our proofs lead to polytime algorithms for constructing colorings that achieve our bounds: O(n²) for line graphs and O(n³m²) for quasi-line graphs. For line graphs, this is faster than the best known algorithm for constructing a coloring that achieves the bound of Reed's original conjecture. [ABSTRACT FROM AUTHOR]

Let Δ (G) be the maximum degree of a graph G. Brooks' theorem states that the only connected graphs with chromatic number X(G) = Δ (G) + 1 are complete graphs and odd cycles. We prove a fractional analogue of Brooks' theorem in this paper. Namely, we classify all connected graphs G such that the fractional chromatic number Xf(G) is at least Δ (G). These graphs are complete graphs, odd cycles, C²8 C5 ⊠ K2, and graphs whose clique number ω(G) equals the maximum degree Δ (G). Among the two sporadic graphs, the graph C²8 is the square graph of cycle C8, while the other graph C5 ⊠ K2 is the strong product of C5 and K2. In fact, we prove a stronger result: If a connected graph G with δ (G) ≥ 4 is not one of the graphs listed above, then we have Xf(G)≤ Δ(G) -- 2/67. [ABSTRACT FROM AUTHOR]

During March 2021, large regions of Eastern Australia experienced prolonged heavy rainfall and extensive flooding. The maximum daily mean column integrated water vapor transport (IVT) over Sydney during this event was within the top 0.3% of all days since 1980, and the 10‐day mean IVT was in the top 0.2%. In this study, we have examined the change in frequency of extreme IVT events over Sydney in 16 climate models from the Coupled Model Intercomparison Project 6 under two Shared Socioeconomic Pathways (SSP245 and SSP585). Generalized Extreme Value modeling was used to further analyze the change in frequency of extreme IVT events. We found the probability of long duration high IVT events is projected to increase by 80% at the end of the century, but the future change in IVT is correlated to the rate of global and regional warming in each model. Plain Language Summary: During March 2021, large regions of Eastern Australia experienced prolonged heavy rainfall and extensive flooding. This was associated with strong horizontal water vapor transport over this region that persisted for approximately 10 days. The amount of water vapor transported over Sydney during this event was extreme and within the top 0.3% of all days since 1980. In this study, we used climate models to project how much more often events such as these may occur by the end of the twenty‐first century under two greenhouse gas emission scenarios. We found that the probability of long duration high water vapor transport over Sydney, as in March 2021, may increase by 80%. Key Points: Sydney's March 2021 floods were associated with persistent high water vapor transportThe probability of long‐duration high integrated water vapor transport events should increase by the end of the twenty‐first centuryDifferences in climate sensitivity within the CMIP6 ensemble may increase the spread of moisture flux projections [ABSTRACT FROM AUTHOR]

The Maritime Continent is a densely populated area of complex topography located between the Pacific and Indian Oceans. It is an area where model skill is particularly important but also difficult to obtain. In this study we examine interannual austral summer rainfall variability in the region and the teleconnection to the El Niño–Southern Oscillation (ENSO) in observation‐based data, reanalyses, and global and regional atmosphere‐only model simulations. We show that model ability to capture interannual rainfall variability is strongly related to model skill in reproducing the ENSO teleconnection to the region, despite strong spatial variability in the ENSO‐rainfall response in coastal areas. Model ability in capturing the spatial pattern of both the midtropospheric moisture and circulation response to ENSO is a strong predictor for model performance in capturing the ENSO‐Maritime Continent rainfall teleconnection. High‐resolution regional simulations and better performing models have opposing ENSO‐rainfall teleconnections between land and sea areas. Plain Language Summary: The Maritime Continent experiences substantial rainfall variability resulting in droughts and flooding. It is also a region of complex topography that is poorly resolved in global climate models. Here we analyze the year‐to‐year rainfall variability of the region in more detail. We find that models that perform well in capturing year‐to‐year variability have more realistic teleconnections to the El Niño–Southern Oscillation (ENSO). Models that have better represented ENSO‐rainfall relationships capture the observed spatial pattern of both the atmospheric moisture and circulation responses to ENSO. A high‐resolution model exhibits much more detailed representation of the atmospheric state with opposing ENSO‐rainfall relationships over land and sea that are not captured by the worst performing global models. The large range in model performance in the region should be considered when making climate projections for the Maritime Continent. Key Points: There is a large range in model skill in capturing interannual Maritime Continent rainfall variabilityMore skillful models capture El Niño–Southern Oscillation (ENSO) teleconnection to midlevel moisture and circulation over regionA high‐resolution regional model shows a different ENSO‐moisture teleconnection over land and sea that is missing from some global models [ABSTRACT FROM AUTHOR]

East-Central Asia is one of the most vulnerable and sensitive regions to climate change, and the variability of extreme precipitation attracts great attention due to the large population and the importance of its economy. Here, three special runs with the Community Earth System Model (CESM) are used to project the changes in representative extreme precipitation indices (Rx1day, Rx5day, R95p, SDII) over East-Central Asia under the 1.5 °C and 2 °C Paris Agreement limits. The results indicate that Rx1day and Rx5day will increase by 28% and 15%, respectively, under the 1.5 °C warming level relative to the historical period (1971–2000). Most areas over East-Central Asia are projected to experience an accelerated increase in response to a further 0.5 °C warming. Specifically, humid areas (HAs) are projected to experience a greater increase in R95p annual days and area fraction, whereas arid and semiarid areas (ASAs) may have threefold higher risks. The proportion of extreme precipitation in total will increase ~10% in most HAs in response to the 0.5 °C additional warming. Holding global warming at 1.5 °C instead of 2 °C reduces the occurrence of R95p annual days by ~3 days/year in humid areas and ~1 day/year in ASAs. For SDII, most HAs will experience 0.2–0.6 mm/day and 0.2–0.4 mm/day increases in 1.5 °C or 2 °C warming limits, especially in Southeast China and the Himalayas. Therefore, limiting global warming to under 1.5 °C is beneficial to reducing the occurrence and associated impact of precipitation extremes in East-Central Asia. [ABSTRACT FROM AUTHOR]

Extreme temperature and precipitation events occurring in Australia in recent decades have caused significant socio-economic and environmental impacts, and thus determining the factors contributing to these extremes is an active area of research. Many recently occurring record-breaking temperature and rainfall events have now been examined from an extreme event attribution (EEA) perspective. This paper describes a set of studies that have examined the causes of extreme climate events using various general circulation models (GCMs), presenting a comprehensive methodology for GCM-based attribution of extremes of temperature and precipitation observed on large spatial and temporal scales in Australia. First, we review how Coupled Model Intercomparison Project Phase 5 (CMIP5) models have been used to examine the changing odds of observed extremes. Second, we review how a large perturbed initial condition ensemble of a single climate model (CESM) has been used to quantitatively examine the changing characteristics of Australian heat extremes. For each approach, methodological details and applications are provided and limitations highlighted. The conclusions of this methodological review discuss the limitations and uncertainties associated with this approach and identify key unexplored applications of GCM-based attribution of extremes. Ideally, this information will be useful for the application of the described extreme event attribution approaches elsewhere. [ABSTRACT FROM AUTHOR]

Abstract: In the last decade, climate mitigation policy has galvanized around staying below specified thresholds of global mean temperature, with an understanding that exceeding these thresholds may result in dangerous interference of the climate system. United Nations Framework Convention on Climate Change texts have developed thresholds in which the aim is to limit warming to well below 2 °C of warming above preindustrial levels, with an additional aspirational target of 1.5 °C. However, denoting a specific threshold of global mean temperatures as a target for avoiding damaging climate impacts implicitly obscures potentially significant regional variations in the magnitude of these projected impacts. This study introduces a simple framework to quantify the magnitude of this heterogeneity in changing climate hazards at 1.5 °C of warming, using case studies of emergent increases in temperature and rainfall extremes. For example, we find that up to double the amount of global warming (3.0 °C) is needed before people in high‐income countries experience the same relative changes in extreme heat that low‐income nations should anticipate after only 1.5 °C of warming. By mapping how much warming is needed in one location to match the impacts of a fixed temperature threshold in another location, this “temperature of equivalence” index is a flexible and easy‐to‐understand communication tool, with the potential to inform where targeted support for adaptation projects should be prioritized in a warming world. [ABSTRACT FROM AUTHOR]

The article examines the influence of anthropogenic forcing on the heat waves in Melbourne, Victoria in January 2014. Topics covered include records high temperature of more than 42 degrees Celsius from January 13 to 18, the influence of human-induced climate change on the likelihood of prolonged periods of extreme heat and analysis of anthropogenic influence using the fraction of attributable risk.

The article focuses on impact of human activity on heat waves experienced in summer 2012/13 in Australia, which experienced its hottest month in January 2013 when temperature reached 36.9 degrees Celsius. Topics discussed include the results of the investigation that made use of the Community Earth System Model's preindustrial control, historical and RCP8.5 experiments, including the rapid increase in high heat wave frequency anomaly in summer 2012/13.

It was recently proved that any graph satisfying [ABSTRACT FROM AUTHOR]

Abstract: We show that every cubic bridgeless graph G has at least perfect matchings. This confirms an old conjecture of Lovász and Plummer. [Copyright &y& Elsevier]

Abstract: An -triangulated graph is a graph in which every odd cycle has two non-crossing chords; -triangulated graphs form a subfamily of perfect graphs. A slightly more general family of perfect graphs are clique-separable graphs. A graph is clique-separable precisely if every induced subgraph either has a clique cutset, or is a complete multipartite graph or a clique joined to an arbitrary bipartite graph. We exhibit a polynomial time algorithm for finding a maximum-weight induced -partite subgraph of an -triangulated graph, and show that the problem of finding a maximum-size bipartite induced subgraph in a clique-separable graph is -complete. [Copyright &y& Elsevier]

This study conducts a detection and attribution analysis of the observed changes in extreme precipitation during 1951–2015. Observed and CMIP6 multimodel simulated changes in annual maximum daily and consecutive 5‐day precipitation are compared using an optimal fingerprinting technique for different spatial scales from global land, Northern Hemisphere extratropics, tropics, three continental regions (North America and western and eastern Eurasia), and global "dry" and "wet" land areas (as defined by their average extreme precipitation intensities). Results indicate that anthropogenic greenhouse gas influence is robustly detected in the observed intensification of extreme precipitation over the global land and most of the subregions considered, all with clear separation from natural and anthropogenic aerosol forcings. Also, the human‐induced greenhouse gas increases are found to be a dominant contributor to the observed increase in extreme precipitation intensity, which largely follows the increased moisture availability under global warming. Plain Language Summary: Human influences have been identified in the observed intensification of extreme precipitation at global and continental scales, but quantifying the contribution of greenhouse gas increases remains challenging. Here, we isolate anthropogenic greenhouse gas impacts on the observed intensification of extreme precipitation during 1951–2015 by comparing observations with CMIP6 individual forcing experiments. Results show that greenhouse gas influences are detected over the global land, Northern Hemisphere extratropics, western and eastern Eurasia, and global "dry" and "wet" regions, which are separable from other external forcings such as solar and volcanic activities and anthropogenic aerosols. The human‐induced greenhouse gas increases are also found to explain most of the observed changes in extreme precipitation intensity, which are consistent with the increased moisture availability with warming. Our results provide the first quantitative evidence for the dominant influence of human‐made greenhouse gases on extreme precipitation increase. Key Points: Causes of the observed intensification of extreme precipitation during 1951 to 2015 are examined using CMIP6 multimodel simulationsResults from optimal fingerprinting analyses show that the anthropogenic signals are robustly detected at hemispheric and continental scalesThe observed increase in extreme precipitation is mostly attributed to anthropogenic greenhouse gas increases [ABSTRACT FROM AUTHOR]

Australian northwest cloudbands (NWCBs) are continental-scale bands of continuous cloud that stretch from northwest to southeast Australia. In earlier studies, where the characteristics of NWCBs and their relationship with precipitation were identified from satellite imagery, there was considerable uncertainty in the results due to limited quality and availability of data. The present study identifies NWCBs from 31 years of satellite data using a pattern-matching algorithm. This new climatology is the longest record based entirely on observations. Our findings include a strong annual cycle in NWCB frequency, with a summer maximum and winter minimum, and a statistically significant increase in annual NWCB days over the period 1984–2014. Physical mechanisms responsible for NWCB occurrences are explored to determine whether there is a fundamental difference between summer and winter NWCBs as hypothesized in earlier studies. Composite analyses are used to reveal that a key difference between these is their genesis mechanisms. Whereas summer NWCBs are triggered by cyclonic disturbances, winter NWCBs tend to form when meridional sea surface temperature gradients trigger baroclinic instability. It was also found that while precipitation is enhanced over parts of Australia during a cloudband day, it is reduced in other regions. During a cloudband day, precipitation extremes are more likely over northwest, central, and southeast Australia, while the probability of extreme precipitation decreases in northeast and southwest Australia. Additionally, cold fronts and NWCBs can interact, leading to enhanced rainfall over Australia. [ABSTRACT FROM AUTHOR]

The original article has been corrected. During proof correction, the author supplied new images that were unfortunately not included. [ABSTRACT FROM AUTHOR]

The likelihood and severity of high‐impact future temperature extremes can be reduced through climate change mitigation efforts. However, meeting the Paris Agreement warming limits requires notably stronger greenhouse gas emissions reduction efforts by major emitters than existing pledges. We examine the impact of Paris‐era decision‐making by the world's three largest greenhouse gas emitters (EU, USA, and China) on projected future extreme temperature events. Country‐level contributions to the occurrence of future temperature extremes are calculated based on current emissions policies and sequential mitigation efforts, using a new metric called the Contribution to Excess Risk Ratio. We demonstrate the Contribution concept by applying it to extreme monthly temperature projections. In many regions, future extremes depend on the current and future carbon dioxide emissions reductions adopted by major emitters. By implementing stronger Paris‐era climate pledges, major emitters can reduce the frequency of future extremes and their own calculated contributions to these temperature extremes. Plain English Summary: Temperature extremes can damage aspects of human society, infrastructure, and our ecosystems. The frequency, severity, and duration of high temperatures are increasing in some regions and are projected to continue increasing with further global temperature increases as greenhouse gas emissions rise. While the international Paris Agreement aims to limit warming through emissions reduction pledges, none of the major emitters has made commitments that are aligned with limiting warming to 2 °C. In this analysis, we examine the impact of the world's three largest greenhouse gas emitters' (EU, USA, and China) current and future decisions about carbon dioxide emissions on the occurrence of future extreme temperatures. We show that future extremes depend on the emissions decisions made by the major emitters. By implementing stronger climate pledges, major emitters can reduce the frequency of future extremes and their own calculated contributions to these temperature extremes. Key Points: The contribution of major greenhouse gas emitters to future temperature extremes is calculatedProjected future extremes depend on current and near‐future CO2 emissions trajectories of the major emittersMajor emitters' calculated contributions to future temperature extremes is reduced through emissions mitigation [ABSTRACT FROM AUTHOR]

The article focuses on the use of a multimethod attribution analysis about the prolonged hydrometeorological drought in northeast Brazil from 2012-2016. It determines possible changes in the hydrometeorological hazard, which comprise the accumulated precipitation, the difference between precipitation and evaporation as well as its potential impact on two basin reservoirs inflows.

The article presents a study which examined the roles of the 2015-2016 El Niño, anthropogenic climate change, and internal atmospheric variability on low rainfall recorded in October 2015 in Tasmania. It mentions that model simulations were used and fraction of attributable risk was calculated. It shows that El Niño and anthropogenic climate change made a significant contributions and the main contributor to the increasing likelihood of low rainfall was atmospheric variability.

A new climate modelling project has been developed for regional climate simulation and the attribution of weather and climate extremes over Australia and New Zealand. The project, known as weather@home Australia- New Zealand, uses public volunteers' home computers to run a moderate-resolution global atmospheric model with a nested regional model over the Australasian region. By harnessing the aggregated computing power of home computers, weather@home is able to generate an unprecedented number of simulations of possible weather under various climate scenarios. This combination of large ensemble sizes with high spatial resolution allows extreme events to be examined with well-constrained estimates of sampling uncertainty. This paper provides an overview of the weather@home Australia- New Zealand project, including initial evaluation of the regional model performance. The model is seen to be capable of resolving many climate features that are important for the Australian and New Zealand regions, including the influence of El Niño-Southern Oscillation on driving natural climate variability. To date, 75 model simulations of the historical climate have been successfully integrated over the period 1985-2014 in a time-slice manner. In addition, multithousand member ensembles have also been generated for the years 2013, 2014 and 2015 under climate scenarios with and without the effect of human influences. All data generated by the project are freely available to the broader research community. [ABSTRACT FROM AUTHOR]

A new climate modelling project has been developed for regional climate simulation and the attribution of weather and climate extremes over Australia and New Zealand. The project, known as weather@home Australia-New Zealand, uses public volunteers' home computers to run a moderate-resolution global atmospheric model with a nested regional model over the Australasian region. By harnessing the aggregated computing power of home computers, weather@home is able to generate an unprecedented number of simulations of possible weather under various climate scenarios. This combination of large ensemble sizes with high spatial resolution allows extreme events to be examined with more robust estimates of uncertainty. This paper provides an overview of the weather@home Australia-New Zealand project, including initial evaluation of the regional model performance. The model is seen to be capable of resolving many climate features that are important for the Australian and New Zealand regions, including the influence of El Niño-Southern Oscillation on driving natural climate variability. To date, 75 model simulations of the observed climate have been successfully integrated over the period 1985-2014 in a time-slice manner. In addition, multi-thousand member ensembles have also been generated for the years 2013, 2014 and 2015 under climate scenarios with and without the effect of human influences. All data generated by the project is freely available to the broader research community. [ABSTRACT FROM AUTHOR]