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There has recently been interest in understanding the differences between specific levels of global warming, especially the Paris Agreement limits of 1.5 °C and 2 °C above pre-industrial levels. However, different model experiments1–3have been used in these analyses under varying rates of increase in global-average temperature. Here, we use climate model simulations to show that, for a given global temperature, most land is significantly warmer in a rapidly warming (transient) case than in a quasi-equilibrium climate. This results in more than 90% of the world’s population experiencing a warmer local climate under transient global warming than equilibrium global warming. Relative to differences between the 1.5 °C and 2 °C global warming limits, the differences between transient and quasi-equilibrium states are substantial. For many land regions, the probability of very warm seasons is at least two times greater in a transient climate than in a quasi-equilibrium equivalent. In developing regions, there are sizable differences between transient and quasi-equilibrium climates that underline the importance of explicitly framing projections. Our study highlights the need to better understand differences between future climates under rapid warming and quasi-equilibrium conditions for the development of climate change adaptation policies. Yet, current multi-model experiments1,4are not designed for this purpose.

The effects of the diurnal cycle and large‐scale atmospheric disturbances dominate rainfall and cloud variability in the Maritime Continent. This study examines the modulation of the Austral Summer diurnal cycle by the Madden–Julian Oscillation (MJO) using cloud populations through precipitation and deep convective cloud derived from satellite measurements. Using Rainfall Potential Areas from Himawari‐8 Advanced Himawari Imager as a proxy for deep convection, our analysis shows that convective clouds are present ∼55% of the time over land in Sumatra during the afternoon and night. Cloud signatures reveal semi‐diurnal structures of deep convective clouds off the West Coast of Sumatra. In contrast, the East Coast exhibits explicit sea‐ward propagation patterns of deep convective controlled by the coastal effects around the Strait of Malacca and Java Sea, together with the influence of synchronized diurnal forcing between islands. We show that the MJO drives the enhanced convective phases, changing the cloud top type distribution, moisture convergence, and moisture transport over the equatorial Indian Ocean. The cold cloud area also increases during the MJO active phases, which is linked to frequent deep convective cloud development near the mountain ranges of Sumatra and the adjacent ocean. The analyses of cloud variations based on the rainfall potential areas and cloud top type provide evidence of the effects of convective processes on the diurnal cycle of ice and water vapor distribution in the troposphere. This study investigates the different weather patterns affecting rainfall and clouds in the Maritime Continent during the Southern Hemisphere summer. Potential areas of deep convective rainfall are derived from the geostationary satellite Himawari‐8. We found that these clouds experience two life cycles in a single day on the West Coast of Sumatra and the open Indian Ocean, while on the East Coast, their patterns are more complex, potentially due to the influence of the surrounding islands. Additionally, we explore how those convective clouds and their properties change in relation to the Madden‐Julian Oscillation (MJO), an equatorial traveling “pulse” of cloud and rainfall from west to east typically recurring every 30–60 days, during the summer season. Our results suggest that the height of the clouds reaches a maximum, and that ice cloud frequency also increases when the MJO is located over the western region of the Maritime Continent. This study contributes to understanding the effects of the MJO and convective clouds in the daily patterns of ice and water vapor in the atmosphere over Sumatra. Rainfall Potential Areas have shown semi‐diurnal structures of deep convective clouds over the Indian OceanAn explicit sea‐ward propagation pattern of deep convective clouds and complex interactions between island were found in the Java SeaThe cloud top height reaches a maximum in the Madden‐Julian Oscillation convective enhanced phase Rainfall Potential Areas have shown semi‐diurnal structures of deep convective clouds over the Indian Ocean An explicit sea‐ward propagation pattern of deep convective clouds and complex interactions between island were found in the Java Sea The cloud top height reaches a maximum in the Madden‐Julian Oscillation convective enhanced phase

Cirrus clouds can strongly affect Earth's radiation balance, but questions remain about their growth mechanisms and rates. Here we show that gravity (buoyancy) waves generated by a storm in Northern Australia on 13 November 2015 caused an observable rippling effect on cirrus clouds up to 1,000 km away, as seen by the recently launched Himawari‐8/9 geostationary satellite. Regional model simulations reproduce the propagation speed of the wave, which agrees with theoretical predictions, and show that the wave amplitude and timing near the tropopause can account for the cirrus modulation. The observed cirrus reach peak optical depths of order 0.3–1.0 and appear roughly in phase with the arrival of the relative humidity maximum, providing new evidence that cirrus clouds can respond rapidly (<30 min) to environmental lifting. Moreover, the edge of a thick anvil cloud attached to the storm itself is observed to expand at the same speed as the wave, showing that the lifting mechanism can also apply to optically thicker ice clouds close to convective centers. Detailed satellite observations and model simulations of a family of convectively generated gravity waves over Northern Australia are shownObservable characteristics of convectively generated gravity waves from the satellite and in the model show good agreementSimulated temperature oscillations are coherent with observed cirrus changes, making this case good for testing ice microphysics

This paper synthesizes and summarizes atmospheric variability on time scales from seconds to decades through a phenomenological census. We focus mainly on unforced variability in the troposphere, stratosphere, and mesosphere. In addition to atmosphere‐only modes, our scope also includes coupled modes, in which the atmosphere interacts with the other components of the Earth system, such as the ocean, hydrosphere, and cryosphere. The topics covered include turbulence on time scales of seconds and minutes, gravity waves on time scales of hours, weather systems on time scales of days, atmospheric blocking on time scales of weeks, the Madden–Julian Oscillation on time scales of months, the Quasi‐Biennial Oscillation and El Niño–Southern Oscillation on time scales of years, and the North Atlantic, Arctic, Antarctic, Pacific Decadal, and Atlantic Multidecadal Oscillations on time scales of decades. The paper serves as an introduction to a special collection of Geophysical Research Letterson atmospheric variability. We hope that both this paper and the collection will serve as a useful resource for the atmospheric science community and will act as inspiration for setting future research directions. The state of the atmosphere is observed to vary naturally on all time scales from seconds to decades and longerThis paper synthesizes and summarizes that variability through a phenomenological censusThe paper provides an authoritative, concise, and accessible point of reference for the most important modes of atmospheric variability

Rainfall during the monsoon in northwest Australia has increased since the 1950s. Previous studies have explored possible causes of the rainfall increase; however, the trend has not been fully explained. Understanding the cause of this trend is important for interpreting climate projections and local water‐sensitive services. We explore the role of the Madden‐Julian Oscillation (MJO) in explaining the rainfall increase. The MJO, since 1974, has had a longer duration in phases associated with enhanced rainfall in northwest Australia (Phases 5 and 6) during the monsoon. We show that the rainfall trend in northwest Australia is identified only during MJO phases associated with enhanced rainfall, with a large change in daily rainfall distribution in these phases. The increasing occurrence of these MJO phases explains most of the rainfall increase, as opposed to an increase in daily rainfall independent of MJO phase, albeit with some sensitivity to MJO definition. Rainfall during the monsoon in northwest Australia has been increasing since the 1950s. In this study, we explore if a semi‐periodic pulse of rainfall and clouds near the equator, known as the Madden‐Julian Oscillation (MJO), may be related to the increased rainfall in the northwest. This pulse of clouds has been found, since 1974, to be spending longer periods of time over northwest Australia. We observed that the increase in MJO duration over northern Australia leads to increasing rainfall in northwest Australia. Rainfall in northwest Australia has been increasing since the 1950s, and the cause of this trend has so far remained unexplainedThe Madden‐Julian Oscillation (MJO) has also been increasingly occurring in phases associated with increased rainfall over northern AustraliaThe increase in MJO convective phases over northern Australia explains most of the increase in rainfall since 1974 in northwest Australia Rainfall in northwest Australia has been increasing since the 1950s, and the cause of this trend has so far remained unexplained The Madden‐Julian Oscillation (MJO) has also been increasingly occurring in phases associated with increased rainfall over northern Australia The increase in MJO convective phases over northern Australia explains most of the increase in rainfall since 1974 in northwest Australia

Evidence indicates that nurses inconsistently engage in evidence-based practice (EBP). This cross-sectional study of 402 nurses at a medical-surgical hospital identifies strategies for augmenting EBP. Nurses’ EBP beliefs scores were higher than their EBP implementation scores. Those with baccalaureate/postgraduate degrees had higher EBP beliefs and implementation scores than those with associate degrees or diplomas. Bedside or direct care nurses were less likely to have baccalaureate/higher degrees and had lower EBP beliefs and implementation scores than did those nurses not serving in direct care roles.

Use of second generation sequencing (SGS) technologies for transcriptional profiling (RNA-Seq) has revolutionized transcriptomics, enabling measurement of RNA abundances with unprecedented specificity and sensitivity and the discovery of novel RNA species. Preparation of RNA-Seq libraries requires conversion of the RNA starting material into cDNA flanked by platform-specific adaptor sequences. Each of the published methods and commercial kits currently available for RNA-Seq library preparation suffers from at least one major drawback, including long processing times, large starting material requirements, uneven coverage, loss of strand information and high cost. We report the development of a new RNA-Seq library preparation technique that produces representative, strand-specific RNA-Seq libraries from small amounts of starting material in a fast, simple and cost-effective manner. Additionally, we have developed a new quantitative PCR-based assay for precisely determining the number of PCR cycles to perform for optimal enrichment of the final library, a key step in all SGS library preparation workflows.

Second-generation sequencing (SGS) has become the preferred method for RNA transcriptome profiling of organisms and single cells. However, SGS analysis of transcriptome diversity (including protein-coding transcripts and regulatory non-coding RNAs) is inefficient unless the sample of interest is first depleted of nucleic acids derived from ribosomal RNA (rRNA), which typically account for up to 95% of total intracellular RNA content. Here we describe a novel microscale hydroxyapatite chromatography (HAC) normalization method to remove eukaryotic and prokaryotic high abundant rRNA species, thereby increasing sequence coverage depth and transcript diversity across non-rRNA populations. RNA-seq analysis of Escherichia coliK-12 and human intracellular total RNA showed that HAC-based normalization enriched for all non-ribosomal RNA species regardless of RNA transcript abundance or length when compared with untreated controls. Microcolumn HAC normalization generated rRNA-depleted cDNA libraries comparable to the well-established duplex specific nuclease (DSN) normalization and Ribo-Zero rRNA-depletion methods, thus establishing microscale HAC as an effective, cost saving, and non-destructive alternative normalization technique.

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. 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%. 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 Sydney's March 2021 floods were associated with persistent high water vapor transport The probability of long‐duration high integrated water vapor transport events should increase by the end of the twenty‐first century Differences in climate sensitivity within the CMIP6 ensemble may increase the spread of moisture flux projections

The U.S. Department of Energy recently announced the first five grants for the Genomes to Life (GTL) Program. The goal of this program is to "achieve the most far-reaching of all biological goals: a fundamental, comprehensive, and systematic understanding of life." While more information about the program can be found at the GTL website (www.doegenomestolife.org), this paper provides an overview of one of the five GTL projects funded, "Carbon Sequestration in Synechococcus Sp.: From Molecular Machines to Hierarchical Modeling." This project is a combined experimental and computational effort emphasizing developing, prototyping, and applying new computational tools and methods to ellucidate the biochemical mechanisms of the carbon sequestration of Synechococcus Sp., an abundant marine cyanobacteria known to play an important role in the global carbon cycle. Understanding, predicting, and perhaps manipulating carbon fixation in the oceans has long been a major focus of biological oceanography and has more recently been of interest to a broader audience of scientists and policy makers. It is clear that the oceanic sinks and sources of CO2 are important terms in the global environmental response to anthropogenic atmospheric inputs of CO2 and that oceanic microorganisms play a key role in this response. However, the relationship between this global phenomenon and the biochemical mechanisms of carbon fixation in these microorganisms is poorly understood. The project includes five subprojects: an experimental investigation, three computational biology efforts, and a fifth which deals with addressing computational infrastructure challenges of relevance to this project and the Genomes to Life program as a whole. Our experimental effort is designed to provide biology and data to drive the computational efforts and includes significant investment in developing new experimental methods for uncovering protein partners, characterizing protein complexes, identifying new binding domains. We will also develop and apply new data measurement and statistical methods for analyzing microarray experiments. Our computational efforts include coupling molecular simulation methods with knowledge discovery from diverse biological data sets for high-throughput discovery and characterization of protein-protein complexes and developing a set of novel capabilities for inference of regulatory pathways in microbial genomes across multiple sources of information through the integration of computational and experimental technologies. These capabilities will be applied to Synechococcus regulatory pathways to characterize their interaction map and identify component proteins in these pathways. We will also investigate methods for combining experimental and computational results with visualization and natural language tools to accelerate discovery of regulatory pathways. Furthermore, given that the ultimate goal of this effort is to develop a systems-level of understanding of how the Synechococcus genome affects carbon fixation at the global scale, we will develop and apply a set of tools for capturing the carbon fixation behavior of complex of Synechococcus at different levels of resolution. Finally, because the explosion of data being produced by high-throughput experiments requires data analysis and models which are more computationally complex, more heterogeneous, and require coupling to ever increasing amounts of experimentally obtained data in varying formats, we have also established a companion computational infrastructure to support this effort as well as the Genomes to Life program as a whole.

Recent data on the physiology of inorganic carbon acquisition by the model marine diatom Thalassiosira weissflogii (Grunow) demonstrate the importance of the catalytic equilibration of HCO3-and CO2by carbonic anhydrases located in the periplasm and in the cytoplasm. These enzymes can use Zn, Co or Cd as their metal centre, and their activity increases at low ambient CO2. The silica frustule provides buffering for extracellular CA activity, The transmembrane transport of CO2 may occur by passive diffusion. Under CO2 limitation, the cytoplasmic HCO3–is used to form malate and oxaloacetic acid via phosphoenolpyruvate carboxylase. It appears that subsequent decarboxylation of these compounds in the chloroplast regenerates CO2 near the site of Rubisco, and thus provides the organism with an effective unicellular C4 photosynthetic pathway. These results, together with other published data, bring up two major questions regarding inorganic carbon acquisition in diatoms: What is the major species of inorganic carbon (CO2 or HCO3–) transported across the membrane under natural conditions? And what is the form of carbon (inorganic or organic) accumulated by the cells?

A well‐defined family of lee waves over southern Tasmania, Australia, is analyzed using a routine radiosonde sounding released from Hobart at 1100 UTC June 18, 1991. Pronounced fluctuations in the ascent rate of the radiosonde are analyzed using a new technique called the horizontal projection method. The dominant horizontal wavelength is found to be 8249 m. An advanced very high resolution radiometer (AVHRR) infrared satellite image at 1554 UTC is used to check this calculation and gives a horizontal wavelength of 8.9±1.4 km. The horizontal projection method takes account of the vertical variation of background flow and the trajectory of the radiosonde. When the Scorer parameter is a strong function of height, as is the case with the 1100 UTC sounding, it is inappropriate to assume that the vertical wavenumber is constant with height. In particular, the vertical wavelength at low levels is about 4.5 km, the waves become evanescent between the heights of 2.5 km and 9 km, and above that the vertical wavelength is typically 10–15 km. As a consistency check, linear wave theory is used to calculate the resonant wave modes supported by the background profiles of wind and potential temperature. These are the wave modes that are most likely responsible for the lee‐wave clouds seen in the AVHRR satellite image. The horizontal wavelength for the resonant wave mode is 8188 m, in agreement with the estimates based on the AVHRR satellite image and from the horizontal projection method. The paper highlights the dangers of interpreting radiosonde soundings as vertical “snapshots” of the atmosphere and assuming that the vertical wavenumber can be characterized by a single value. It is shown that treating the radiosonde sounding as a vertical profile and analysing wave‐like structures in the ascent rate using standard spectral methods gives an incorrect vertical wavelength of 1906±238 m. The paper concludes that operational radiosonde soundings can be used to make accurate, quantitative measurements of orographically generated waves, provided that the vertical variation in the background flow and the motion of the radiosonde through the wave field are taken into account.

Organized mesoscale convection is important for many atmospheric phenomena and hazards, however the understanding of its governing mechanisms is incomplete. Theories explaining mesoscale organization rely on the interaction between convection outflows and lower‐tropospheric wind shear. Here a new mechanism is presented, where lower‐stratospheric wind shear is shown to influence mesoscale organization. The mechanism is linked to coupling between convection and gravity waves, with the stratosphere playing a role in shaping the tropospheric wave spectrum. The key result is that lower‐stratospheric shear creates a preference for organized systems propagating in the same direction as the shear vector by weakening the systems propagating in the opposite direction to the shear. This result has important implications for stratosphere‐troposphere interactions, numerical modeling, and understanding of convective organization in general. Many people think thunderstorms are amazing and numerous scientists spend their lives researching them because they are important for weather and climate. It might therefore be surprising that we don't fully understand how thunderstorms form. We know what's important to make clouds grow, like the way the temperature and water vapor changes with altitude. But something else has to happen to make clouds become thunderstorms. What we typically teach at university is that cold air falls out the bottom of clouds, pushing the near‐surface air upwards to make new clouds. If the wind near the surface changes with altitude in just the right way, the new clouds will form thunderstorms. Most meteorologists are happy with this theory, but it doesn't work all the time. Here I use a simplified computer model to show that the wind above the clouds can affect thunderstorm behavior. The storms create ripples in the wind that travel upwards. Then the wind above the clouds reflects the ripples back downwards where they affect the storms' lifecycle. This is a complex process, and we need to spend more time searching for it in real data and in more complicated computer models to see how often it occurs in the real world. Idealized simulations demonstrate that the mesoscale organization of convection can be affected by lower‐stratospheric wind shearThere is a preference for mesoscale convective systems to propagate in the same direction as the lower‐stratospheric wind shear vectorThe results provide insight into a new mechanism for organized convection and stratosphere‐troposphere interactions Idealized simulations demonstrate that the mesoscale organization of convection can be affected by lower‐stratospheric wind shear There is a preference for mesoscale convective systems to propagate in the same direction as the lower‐stratospheric wind shear vector The results provide insight into a new mechanism for organized convection and stratosphere‐troposphere interactions

Atmospheric rivers (ARs) are elongated narrow bands of enhanced water vapor that can cause intense rainfall and flooding. ARs only appeared in the literature the last 30 years, and there has been much debate about how to define ARs and how to identify them. As a result, a wide range of AR identification algorithms have been produced with variations in the conditions required for an object to be classified as an AR and differences in the input data. One of the key conditions in most AR identification algorithms is a minimum threshold of water vapor flux, along with geometric criteria. The aim of this study is to explore uncertainties in global AR identification based on a single integrated water vapor transport (IVT)‐based identification method. We conduct a sensitivity analysis under one algorithmic framework to explore the effects of different IVT thresholds, input data resolutions, and regridding methods during the Years of Tropical Convection operational analysis (May 2008 to April 2010). We found that the resolution and regridding method affects the number of ARs identified but the seasonal cycle is maintained. AR identification is highly sensitive to the choice of IVT threshold; importantly, the commonly used 250 kg m−1s−1IVT threshold is not appropriate for global studies with detection methods that also include a restrictive geometric condition as this combination can lead to the strongest systems failing to be identified. The uncertainties within a single AR detection method and input data parameters may be as large as uncertainties across AR detection methodologies. Atmospheric rivers (ARs) are large corridors of increased moisture flow in the lower atmosphere. ARs can cause hazards such as heavy rainfall, damaging winds, landslides, and flash flooding. Recently, there has been a lot of discussion about how scientists should define these weather phenomena; for example, what is the minimum amount of water needed for a weather system to be considered an AR? In order to study ARs, scientists often look at large data sets over multiple decades. So instead of searching for ARs manually in these huge data sets, they create computer algorithms that identify ARs automatically. As a result, there has been a large variety of different algorithms developed. Using a single algorithm, we answer the following question: How do small differences between data sets and moisture content of ARs affect the detection results? We found that when ARs are defined using lower thresholds of vapor transport and geometric conditions, algorithms may fail to identify the strongest ARs. Additionally, we quantified some of the uncertainty associated with using data sets of different fidelity. These results are useful for helping scientists choose the best threshold and data sets for their study. An IVT‐based identification method was used to perform extensive sensitivity tests on IVT threshold and data set parameters (resolution and regridding)IVT thresholds below 350 kg m−1s−1may miss the strongest ARs when combined with a geometric criterionSimple methodological changes to resolution, order of operations, regridding methods, and IVT threshold can result in considerable changes to the detection results

The impact of cold pools on line‐orientated convective systems is assessed using idealized simulations of tropical oceanic convection under weak, moderate, and strong wind shear regimes. Cold pools are weakened by suppressing evaporation in the shallow subcloud layer. Analysis of objectively identified convective systems reveals that the convection with weaker cold pools is more often oriented parallel, rather than perpendicular, to the wind shear. The cold pool‐induced orientation changes are most pronounced in the strong shear environment. Interactions between convective orientation and the tropical atmosphere are assessed. Simulations with shear‐parallel convection demonstrate more top‐of‐atmosphere upwelling longwave radiation and less reflected shortwave radiation due to changes in convective anvils, faster‐propagating larger‐scale gravity waves, narrower cross‐shear moisture distributions, and differences in convective momentum fluxes. The results highlight critical interactions across convective scales, mesoscales, and climate scales, as well as avenues for parameterizing structural modes of mesoscale‐organized convection in global models. Over tropical oceans, individual thunderstorms often cluster together into a collection of thunderstorms. The way in which these thunderstorm clusters are organized is important for many aspects of weather and climate. For example, for line‐organized thunderstorm clusters, whether the line is oriented parallel or perpendicular to the winds is important for how the thunderstorms alter the winds and how their anvils reflect solar radiation. In this study, we investigate the influence of cold pools, which are evaporatively cooled regions of air near the surface below thunderstorms, on the orientation of line‐organized thunderstorm clusters using computer model simulations. We find that line‐organized thunderstorm clusters are oriented parallel to the winds more often when the cold pools are weaker. We also show that cold pools have a larger impact on the orientation of the thunderstorm line when the upper level winds are stronger. Finally, we show how the cold pool‐induced changes to line‐organized thunderstorms affect the tropical climate, meaning these effects are important for climate models. Idealized simulations of tropical oceanic convective systems with varying wind profiles are analyzedWhen cold pools are weakened, convective systems are more often oriented shear‐parallel, especially under strong wind shear regimesShear‐parallel versus perpendicular orientation impacts cloud‐radiation interactions, gravity waves, and precipitable water patterns