Atmospheric science

  • Article
    | Open Access

    Sea spray aerosol (SSA) are an important way through which oceans can influence the atmosphere’s radiative properties. Here, the authors present measurements taken over a 42,000 km ship cruise in the Atlantic and Pacific Ocean and show that SSA number concentrations vary over a 24-hour cycle, possibly linked to surface water bubble-bursting dynamics.

    • J. Michel Flores
    • , Guillaume Bourdin
    •  & Ilan Koren
  • Article
    | Open Access

    How much the potential intensity of tropical cyclones (TCs) increases in warmer environments is not well known. Here, the authors show that TC rainfall rates have increased by 1.3% per year between 1998 and 2018, a trend that is mainly driven by stronger rainfall in the outer-core region of TCs.

    • Oscar Guzman
    •  & Haiyan Jiang
  • Article
    | Open Access

    How climate change influences the lifecycle of stratospheric volcanic aerosols and the associated radiative forcing is unknown. Here, the authors present model experiments suggesting that climate change amplifies the forcing of large-magnitude tropical eruptions but reduces the forcing of moderate-magnitude tropical eruptions.

    • Thomas J. Aubry
    • , John Staunton-Sykes
    •  & Anja Schmidt
  • Article
    | Open Access

    Satellite observations reveal a significant positive trend in Earth’s energy imbalance, but the contributing drivers have yet to be understood. Here, the authors show that it is exceptionally unlikely that this trend can be explained by internal variability; instead, anthropogenic forcing and feedbacks cause the trend.

    • Shiv Priyam Raghuraman
    • , David Paynter
    •  & V. Ramaswamy
  • Article
    | Open Access

    How the Central American mountains influence tropical cyclone (TC) development in the eastern North Pacific is not well understood. Here, the authors use model simulations to show that on a seasonal timescale, these mountains interrupt moisture transport from the Caribbean Sea and as a result, reduce TC activity by up to 35%.

    • Dan Fu
    • , Ping Chang
    •  & Hylke E. Beck
  • Perspective
    | Open Access

    Many different methods have been developed to forecast climate phenomena like the El Nino-Southern Oscillation (ENSO) which makes a fair comparison of their capabilities crucial. In this perspective, the authors discuss how choices in the evaluation method can lead to an overestimated perceived skill of ENSO forecasts.

    • James S. Risbey
    • , Dougal T. Squire
    •  & Carly R. Tozer
  • Article
    | Open Access

    How tropical cyclones have varied in intensity and frequency in the past is not well known as longer records are rare. Here, the authors show that changes in observing practices explain the recorded century scale increase in Atlantic major hurricane frequency, and recent increases are not part of a century-scale trend.

    • Gabriel A. Vecchi
    • , Christopher Landsea
    •  & Thomas Knutson
  • Article
    | Open Access

    Despite a ban on ozone depleting substances, ozone depletion during cold winters in the Arctic stratosphere has been increasing in recent decades. Here, the authors show conditions favourable for Arctic ozone depletion could worsen as a response of stratospheric temperature and water to continued release of greenhouse gases.

    • Peter von der Gathen
    • , Rigel Kivi
    •  & Markus Rex
  • Article
    | Open Access

    Understanding the uncertainties associated with urban heat wave (UHW) projection is critical for local actions to mitigate extreme heat risks in cities. Here, the authors show that choices of model structural design contribute a large proportion of the uncertainty in projecting UHWs under climate change.

    • Zhonghua Zheng
    • , Lei Zhao
    •  & Keith W. Oleson
  • Article
    | Open Access

    Satellite-based estimates of radiative forcing by aerosol–cloud interactions are consistently smaller than those from global models, hampering accurate projections of future climate change. Here, the authors show that the discrepancy can be substantially reduced by correcting sampling biases induced by inherent limitations of satellite measurements.

    • Hailing Jia
    • , Xiaoyan Ma
    •  & Johannes Quaas
  • Article
    | Open Access

    It has been suggested that sea surface temperatures in the North Tropical Atlantic exert strong influence on the evolution of the El Nino Southern Oscillation (ENSO). Here, the authors argue that observed statistics are fully consistent with ENSO driving climate variations in the Atlantic and not vice versa.

    • Wenjun Zhang
    • , Feng Jiang
    •  & Axel Timmermann
  • Article
    | Open Access

    The Madden-Julian Oscillation (MJO) is a crucial component of the tropical weather system, but forecasting it has been challenging. Here, the authors present a deep learning bias correction method that significantly improves multi-model forecasts of the MJO amplitude and phase for up to four weeks.

    • H. Kim
    • , Y. G. Ham
    •  & S. W. Son
  • Article
    | Open Access

    The production of chlorofluorocarbons (CFC) was phased-out under the Montreal, but renewed emissions of CFC-11 have been reported recently. Here, the authors present a joint analysis of multiple factors and find that emissions of CFC-11, but also CFC-12 and CFC-113 are higher than expected, indicating renewed emissions.

    • Megan Lickley
    • , Sarah Fletcher
    •  & Susan Solomon
  • Article
    | Open Access

    Long-range predictions of the Asian summer monsoon remain challenging due to its complex atmosphere–land–ocean interactions. Here, the authors show that a large ensemble of model simulations can predict the Asian summer monsoon and associated summer tropical cyclone activity more than one year ahead.

    • Yuhei Takaya
    • , Yu Kosaka
    •  & Shuhei Maeda
  • Article
    | Open Access

    How the rainfall intensity of tropical cyclones changes with climate change is not well known. Here, the authors show that while the rain rate in the outer region of TCs is clearly increasing between 1999 and 2018, it decreases significantly in the inner-core of TCs during 1999-2018.

    • Shifei Tu
    • , Jianjun Xu
    •  & Long S. Chiu
  • Article
    | Open Access

    El Niño-Southern Oscillation (ENSO) is a key mode of climate variability with worldwide climate impacts. Here, the authors show that improved representation of summer equatorial Atlantic variability and its lagged teleconnection mechanism with the Pacific, relates to enhanced predictive capacity of autumn/winter ENSO.

    • Eleftheria Exarchou
    • , Pablo Ortega
    •  & Chloé Prodhomme
  • Article
    | Open Access

    The Antarctic Peninsula sees some of the strongest warming of the whole continent over the last decades, the drivers of which are not well known. Here, the authors show that winter sea surface temperature increases in the Tasman sea lead to changes in Southern Ocean storm tracks that in turn warm the Antarctic Peninsula.

    • Kazutoshi Sato
    • , Jun Inoue
    •  & Irina Rudeva
  • Article
    | Open Access

    Atmospheric rivers are responsible for much of the poleward water vapour transport in the mid-latitudes and can cause extreme precipitation after landfall. Here, the authors show that ocean fronts and eddies can influence atmospheric rivers and increase the associated precipitation along the North American west coast.

    • Xue Liu
    • , Xiaohui Ma
    •  & Christina M. Patricola
  • Article
    | Open Access

    The regulation of aircraft engine NOx emissions was introduced to improve local air quality and reduce NOx emissions at altitude. Here, the authors find that greater fuel efficiency of aircrafts, and therefore lower CO2 emissions, could be preferable to reducing NOx emissions in terms of the aviation industries future climate impacts.

    • Agnieszka Skowron
    • , David S. Lee
    •  & Bethan Owen
  • Article
    | Open Access

    Globally, new particle formation represents a major source of cloud condensation nuclei. Here, the authors present evidence of frequent occurrence of new particle formation in the upper part of remote marine boundary layer following cold front passages.

    • Guangjie Zheng
    • , Yang Wang
    •  & Jian Wang
  • Article
    | Open Access

    The relative roles of the ocean and atmosphere for the Atlantic Niño is poorly understood. Here, we show that its seasonality is governed by atmospheric diabatic heating that is associated with the seasonal migration of the inter-tropical convergence zone.

    • Hyacinth C. Nnamchi
    • , Mojib Latif
    •  & Ingo Richter
  • Article
    | Open Access

    Wildfires produce aerosols known to impact the climate, but the wider-reaching effects of this biomass burning are poorly constrained in models. Here the authors use a suite of observations from 12 campaigns around the globe to determine that the values used by most climate models overestimate the contribution of biomass burning aerosols.

    • Hunter Brown
    • , Xiaohong Liu
    •  & Duli Chand
  • Article
    | Open Access

    Human emissions are thought to have caused an increase in wildfire risk, but how different emission sources contribute is less well known. Here, the authors show that the increase due to greenhouse gas emissions was balanced by aerosol-driven cooling, an effect that is projected to disappear during the 21st century.

    • Danielle Touma
    • , Samantha Stevenson
    •  & Sloan Coats
  • Article
    | Open Access

    The potential contribution of Greenland Ice Sheet to sea level rise in the future is known to be substantial. Here, the authors undertake new modelling showing that the Greenland Ice Sheet sea level rise contribution is 7.9 cm more using the CMIP6 SSP585 scenario compared to CMIP5 using multiple RCP8.5 simulations.

    • Stefan Hofer
    • , Charlotte Lang
    •  & Xavier Fettweis
  • Article
    | Open Access

    Many climate models failed to reproduce the eastern Pacific cooling that has been linked to slower warming in the early 20th century. Here, the authors present a feedback mechanism between the tropical Pacific and the Atlantic which contributes to this bias as it further dampens the Pacific cooling response in models.

    • Chen Li
    • , Dietmar Dommenget
    •  & Shayne McGregor
  • Article
    | Open Access

    Solar insolation is not equally distributed on the Earth’s surface and such imbalances influence the atmospheric circulation. Here, the authors show that latitudinal insolation gradients synchronized the hydroclimate in the Northern mid-latitudes and the African and South American Monsoons throughout the Holocene.

    • Michael Deininger
    • , Frank McDermott
    •  & Denis Scholz
  • Article
    | Open Access

    Monsoon systems have strong impacts on precipitation and food security over large areas of the world. Here, the authors show that plant responses to rising CO2 concentrations in the atmosphere play a key role in modulating seasonal rainfall and water resources over global land monsoon regions.

    • Jiangpeng Cui
    • , Shilong Piao
    •  & Gabriel J. Kooperman
  • Article
    | Open Access

    The COVID-19 pandemic has stopped many human activities, which has had significant impact on emissions of greenhouse gases. Here, the authors present daily estimates of country-level CO2 emissions for different economic sectors and show that there has been a 8.8% decrease in global CO2 emissions in the first half of 2020.

    • Zhu Liu
    • , Philippe Ciais
    •  & Hans Joachim Schellnhuber
  • Article
    | Open Access

    Unconventional oil and gas production has increased drastically in the US, but its environmental impacts are not well known. Here, the authors show that these wells can be associated with elevated levels of airborne particle radioactivity in downwind locations.

    • Longxiang Li
    • , Annelise J. Blomberg
    •  & Petros Koutrakis
  • Article
    | Open Access

    How the abrupt warming events recorded in Greenland ice cores during the last glacial cycle have influenced the tropical climate is not well known. Here the authors present new lake sediment data from the Peruvian Andes that shows that these events resulted in rapid glacier retreat and large reductions in lake level.

    • Arielle Woods
    • , Donald T. Rodbell
    •  & Joseph S. Stoner
  • Article
    | Open Access

    Ice nucleating particles impact the global climate by altering cloud formation and properties, but the sources of these emissions are not completely characterized. Here, the authors show that secondary organic aerosols formed from the oxidation of organic gases in the atmosphere can be a source of ice nucleating particles.

    • Martin J. Wolf
    • , Yue Zhang
    •  & Daniel J. Cziczo
  • Article
    | Open Access

    Which vapors are responsible for new particle formation in the Arctic is largely unknown. Here, the authors show that the formation of new particles at the central Arctic Ocean is mainly driven by iodic acid and that particles smaller than 30 nm in diameter can activate as cloud condensation nuclei.

    • Andrea Baccarini
    • , Linn Karlsson
    •  & Julia Schmale
  • Article
    | Open Access

    Dryness stresses vegetation and can lead to declines in productivity, increased emission of carbon, and plant mortality, but the drivers of this stress remain unclear. Here the authors show that soil moisture plays a dominant role relative to atmospheric water demand over most global land vegetated areas.

    • Laibao Liu
    • , Lukas Gudmundsson
    •  & Sonia I. Seneviratne
  • Article
    | Open Access

    A significant part of the subpolar North Atlantic has warmed less over the past century than the rest of the global ocean, a feature called the North Atlantic warming hole. Here, the authors show that this anomaly can be explained by remote atmospheric forcing from the rapidly warming Indian Ocean.

    • Shineng Hu
    •  & Alexey V. Fedorov
  • Article
    | Open Access

    Proxy reconstructions show a decreasing trend from the Middle to Late Holocene, which conflicts with model results showing an increasing trend. Statistical analysis of model output shows that these conflicting results originate from two distinct modes of variability, which dominate at different regions and times.

    • Jürgen Bader
    • , Johann Jungclaus
    •  & Martin Claussen
  • Article
    | Open Access

    Extreme events high up in the winter stratosphere are known to influence our weather and their predictability has potential to improve seasonal weather forecasts. Here, the authors examine factors that influence their generation and highlight a previously unrecognised sensitivity to the upper equatorial stratosphere.

    • L. J. Gray
    • , M. J. Brown
    •  & J. Anstey
  • Article
    | Open Access

    The methane emissions from natural gas vehicles (NGVs) are unclear. Here the authors report high methane emissions from heavy-duty NGVs, and by using a scenario analysis show that strictly implementing the upcoming China VI standard could reduce GHG emissions by 509 Mt CO2eq for 2020-2030.

    • Da Pan
    • , Lei Tao
    •  & Mark A. Zondlo
  • Article
    | Open Access

    The spatial pattern and global mean values of warming differ between different climate models, an issue that needs to be better understood in order to obtain reliable regional projections. Here, the authors show that ice-albedo and water vapor feedbacks are the key processes that are responsible for this inter-model spread.

    • Xiaoming Hu
    • , Hanjie Fan
    •  & Song Yang
  • Article
    | Open Access

    Dust emissions are likely to increase significantly when land vegetation is absent, such as during the Precambrian period. Here, the authors use climate simulations to find that high dust emissions in the Precambrian could have cooled the global climate by ~10 °C.

    • Peng Liu
    • , Yonggang Liu
    •  & Yongyun Hu
  • Article
    | Open Access

    The asymmetry between El Niño and La Niña episodes in the tropical Pacific is often not well represented in models. Here, the authors show that this asymmetry is related to subsurface nonlinear dynamical heating and that a realistic representation of this process can potentially improve tropical climate projections.

    • Michiya Hayashi
    • , Fei-Fei Jin
    •  & Malte F. Stuecker