The Copernicus Twitter account as well as all Twitter accounts of journals published by us have been deactivated. There will be no automatic feeds of newly posted preprints or published journal articles anymore, we do not actively tweet, and the status informs that the accounts are no longer maintained. Twitter is no longer linked from the journal websites or in the share section of the preprint or journal article HTML pages.

The production of steel coincides with large emissions of greenhouse gases and air pollutants including carbon monoxide. European facilities are required to report their emissions, which are estimated using a variety of methods. The authors evaluate these estimates using carbon monoxide concentrations measured via satellite. Read more.

We are pleased to announce that scientists associated with our 38 library partners representing 350 universities and research centres as well as 300 institutions from Research4Life countries will be informed directly about APC coverage when browsing our articles on ResearchGate. Read more.

We are pleased to announce a change in the handling of article processing charges. Please find all information on our APC page as well as in the news item from EGU.

Extreme Saharan dust events expanded northward to the Atlantic and Europe, prompting record-breaking PM₁₀ and PM_2.5 events. Please read more.

This study uses 3D-printed ice crystal analogues falling in a water–glycerine mix and observed with multi-view cameras, simulating atmospheric conditions. Four types of motion are observed: stable, zigzag, transitional, and spiralling. Particle shape strongly influences motion; complex shapes have a wider range of conditions where they fall steadily compared to simple plates. Read more.

The rapid global warming of 2023 has led to concerns that it could be externally driven. Here the authors show that climate models subject only to internal variability predict such warming spikes but rarely (p~1.6 %). However, when a prolonged La Niña immediately precedes an El Niño, as occurred leading up to 2023, such spikes are not uncommon (p~10.3 %). Read more.

You have worked hard to get your results, analyse the data, and draw conclusions from your research topic. Now it is time to write up! Please find information on EGU's webinar "How to write a research paper" here.

Copernicus is pleased to announce a new collaboration with ResearchGate in the framework of ResearchGate's Journal Home programme. Please read Copernicus' official announcement and have a look at ACP's profile page for more details.

ACP now offers a co-review option for referees. Please read more.

The journal metrics 2023 were released. Please find further information on the journal metrics page.

This paper presents direct evidence from space (solely based on observations) that CO₂ increase leads to the theoretically expected effects on longwave spectral radiances. This is achieved by using a methodology that allows us to isolate the CO₂ effects from the temperature and water vapor effects. Read more.

The high quality and success of ACP greatly depend on the huge voluntary contributions of expert referees and editors. In recognition of exceptional contributions in these capacities, ACP is pleased to announce the recipients of the Outstanding Referee and Editor Awards 2023. Read more.

Copernicus Publications is delighted to announce a new agreement with the Swedish National Consortium, Bibsam. Through the agreement, authors affiliated with Bibsam member institutions benefit from the direct settlement of article-processing charges (APCs) in all journals published by Copernicus Publications. Read more.

The 2023 ACP Paul Crutzen Publication Award has been presented to recognize two outstanding publications in ACP that advance our understanding of atmospheric chemistry and physics. Read more.

ACP has recruited 19 new editors to strengthen the editorial board across all journal subject areas. Read more.

The authors present a novel mechanism of how regional anomalies in water vapour concentrations in the upper troposphere and lower stratosphere impact regional atmospheric circulation systems. Read more.

Tools based on artificial intelligence (AI) are increasingly being used to create scientific documents, including peer-reviewed publications, preprints and conference contributions. Please read EGU's statement on the use of such tools in publications.

We are sad to announce the passing of Thomas von Clarmann, a dedicated, long-time journal editor for Atmospheric Chemistry and Physics and Atmospheric Measurement Techniques. Being passionate about interdisciplinary open-access publishing, he also played a key role as one of the initiators and executive editors of the Encyclopedia of Geosciences. Thomas will be missed by the scientific community as a valued friend, excellent colleague, and inspiring leader. Our heartfelt condolences go to Thomas' family, friends, and colleagues.

Copernicus Publications started using the Research Organization Registry (ROR) database as the framework to assign institutional identifiers to corresponding authors in order to disambiguate affiliations listed on a published article and greatly enhancing the reporting capabilities to all academic stakeholders. Please read more.

We would like to say a huge thank you to all referees for their volunteer efforts to provide fair, thorough, and constructive peer-review reports. Their invaluable contribution maintains our high scientific standards and ensures the ongoing success of our interactive open-access journals.

ACP is seeking editors to strengthen its editorial board in all journal subject areas. Please read more.

We are pleased to announce the appointment of 18 new editors in the subject area of climate physics. The appointments follow a strategic decision by the journal to offer the community greater coverage of physical climate science, including cloud physics, atmospheric dynamics, boundary layer turbulence, precipitation processes, the water cycle and climate feedback processes. Please read more.

Congratulations to Xiaohong Liu and Uli Pöschl for being elected as American Geophysical Union (AGU) Fellows! Xiaohong has been recognized for his exceptional contributions to the understanding of the fundamental mechanisms of aerosol impacts on clouds and climate and advancing atmospheric models. Uli has received this honour for his transformative contributions to the understanding of atmospheric multiphase processes and their impacts on the Earth system and public health. Their election as AGU Fellows demonstrates the high recognition and reputation of our editorial board members in the global atmospheric science community.

The 2022 ACP Paul Crutzen Publication Award has been presented to recognize an outstanding publication in ACP that advances our understanding of atmospheric chemistry and physics. Read more.

Fuel sulfur regulations were implemented for ships in 2020 to improve air quality but may also accelerate global warming. We use spatial statistics and satellite retrievals to detect changes in the size of cloud droplets and find evidence for a resulting decrease in cloud brightness within a major shipping corridor after the sulfur limits went into effect. Our results confirm both that the regulations are being followed and that they are having a warming influence via their effect on clouds. Read more.

The journal metrics 2022 were released. Please find further information on the journal metrics page.

To offer our journal editors a better service and an improved experience in our online system, we have significantly improved the referee nomination tool in our review system Copernicus Office Editor. Experience more and take a look.

ACP is seeking editors to join its editorial board to help expand the coverage of topics in the broad area of climate physics. Please read more.

Looking to gain experience and boost your confidence as a referee? Apply for the EGU peer review training, and gain valuable insights into the peer review process. EGU is offering FREE online training in which you'll learn about the role of peer review in the publication process, in addition to review criteria and open peer review, and get hands-on experience in writing reviews. To find out more and apply, visit https://www.egu.eu/news/967/egu-peer-review-training-workshop-apply-now/.

The success of ACP heavily relies on the huge commitment of volunteers that dedicate their time and expertise as referees and editors. To recognize particularly outstanding contributions in these efforts, ACP introduced this year awards for Outstanding Referees and Outstanding Editor. Read more.

Congratulations to our editor Guangjie Zheng, who will receive the 2023 Outstanding Early Career Scientist Award of the Atmospheric Sciences Division at the upcoming EGU General Assembly. Guanjie joined the ACP editorial board in 2022 and since then has provided her expertise of atmospheric multiphase chemistry processes to handle papers in the subject areas aerosols, clouds and precipitation, dynamics, and gases. If you attend EGU23, join the award lecture on Thu, 27 Apr 2023, 19:00.

The impact of aerosols on clouds is one of the largest uncertainties in the human forcing of the climate. Aerosol can increase the concentrations of droplets in clouds, but observational and model studies produce widely varying estimates of this effect. The authors show that these estimates can be reconciled if only polluted clouds are studied, but this is insufficient to constrain the climate impact of aerosol. The uncertainty in aerosol impact on clouds is currently driven by cases with little aerosol. Read more.

In the coming days and weeks, readers of our journals will experience a facelift of our websites. Read more about the background.

We are sad to announce that the Atmospheric Chemistry and Physics community has lost a highly valued member: Prof Astrid Kiendler-Scharr passed away in February 2023. Please read our obituary.

The number of cloud droplets per unit volume is a significantly important property of clouds that controls their reflective properties. Computer models of the Earth's atmosphere and climate have low skill at predicting the reflective properties of Southern Ocean clouds. Here the authors investigate the properties of those clouds using satellite data and find that the cloud droplet number and cloud albedo in the Southern Ocean are related to the oceanic phytoplankton abundance near Antarctica.

After 20 years of pioneering its highly successful publication model with interactive discussion and open peer review in its discussion forum ACPD, ACP reached out to EGUsphere in 2022 allowing additional submission routes with preprint discussions outside of ACPD. As of today, discussions of ACP manuscripts will only take place on EGUsphere.

Copernicus Publications is delighted to announce a new agreement with the UK-based Jisc (Joint Information Systems Committee) to streamline open-access publishing for their members. Read more.

The origins of the abundant cloud condensation nuclei (CCN) in the upper troposphere (UT) of the Amazon remain unclear. With model developments of new secondary organic aerosol schemes and constrained by observation, the authors show that strong aerosol nucleation and condensation in the UT is triggered by biogenic organics, and organic condensation is key for UT CCN production.

New particle formation (NPF) is a source of atmospheric aerosol number concentration that can impact climate by growing to larger sizes and under proper conditions form cloud condensation nuclei (CCN).

Peering inside common atmospheric particles is providing important clues to their climate and health effects, according to a new study by University of British Columbia chemists. Read more.

The first annual ACP Paul Crutzen Publication Award has been presented to recognize an outstanding publication in ACP that advances our understanding of atmospheric chemistry and physics. Read more.

Conference of the European Geosciences Union (EGU) at the Max Planck Institute for Chemistry explores ways to further develop and promote interactive open-access publishing with transparent peer review and public discussion. Read more.

Pollution particles cool climate and offset part of the global warming. However, they are washed out by rain and thus their effect responds quickly to changes in emissions. The authors show multiple datasets to demonstrate that aerosol emissions and their concentrations declined in many regions influenced by human emissions, as did the effects on clouds.

It was September 2001 when the first preprint was posted for public peer review and interactive public discussion in ACP. Time to celebrate!

The ETH Domain institutions PSI, Empa, Eawag, WSL and Copernicus Publications have signed an agreement on the central settlement of article processing charges (APCs).

From now on, manuscripts that involve funding from the Swiss National Science Foundation (SNSF) or the Luxembourg National Research Fund (FNR) will benefit from direct settlement of article processing charges (APCs).

After 21 years as executive editors of ACP, Uli Pöschl and Thomas Koop have stepped down from day-to-day leadership of the journal and will take up positions on the journal's advisory board. Ken Carslaw and Barbara Ervens will continue as co-chief executive editors. Ken was one of the co-founding editors in 2001, and Barbara joined the executive committee in 2019 following nine years as a regular editor. Read more.

University of Exeter Library and Copernicus Publications have signed an agreement on the central billing of article processing charges (APCs) to facilitate the publication procedure for authors.

The journal metrics 2021 were released and the current numbers are available from the journal metrics overview.

Today the European Geosciences Union and Copernicus Publications are announcing sweeping new changes, that will give our authors the ability to make vital alterations to their names in previously published scientific literature. This new policy will allow authors to retrospectively update previous publications with their current names, including conference abstracts, preprints, and peer-reviewed articles.

Offline analyses of the hygroscopicity and composition of atmospheric aerosols are complementary to online analyses in view of the applicability to broader sizes, specific compound groups, and investigations at remote sites. This offline study characterized the composition of water-soluble matter in aerosols and their humidity-dependent hygroscopicity on Okinawa, a receptor site of East Asian outflow.

To ensure that ACP continues to represent the growing global community of atmospheric scientists that it serves, we deliberately invited colleagues who bring expertise from a wide range of countries. Read more.

The authors have undertaken atmospheric iodine monoxide (IO) observations in the global marine boundary layer with a wide latitudinal coverage and sea surface temperature (SST) range. They conclude that atmospheric iodine is abundant over the Western Pacific warm pool, appearing as an iodine fountain, where ozone (O₃) minima occur.

EGUsphere, the innovative open-access repository created by the European Geosciences Union and Copernicus Publications, is growing. For the first time, authors will be able to upload preprints to the online resource, taking advantage of EGU’s pioneering public peer-review process, whilst preparing their papers for future release.

At the end of the year, we would like to express our deep gratitude for our collaboration with all editors, referees, and authors in 2021. Please take a look at our Christmas card. Since our virtual office is closed from 23 Dec to 2 Jan and a significant number of editors and referees pause their work over the Christmas days, we extended all journal review deadlines: deadlines expiring shortly before or over Christmas have been extended to the week after and deadlines expiring after Christmas or over New Year have been extended to after New Year’s Day. Season's greetings and a happy New Year. Please stay healthy.

Ammonia (NH₃) gas emitted from soils and biomass burning contributes to particulate air pollution. The authors used satellite observations of the atmosphere over Africa to show that declines in NH₃ concentrations over South Sudan's Sudd wetland in 2008–2017 are related to variation in wetland extent.

Vertical profiles of black carbon (BC) in the Arctic were measured during the PAMARCMiP aircraft-based experiment in spring 2018 and compared with those observed during previous aircraft campaigns in 2008, 2010, and 2015.

Aerosol particle pH is well-buffered by alkaline compounds, notably NH₃ and crustal elements. NH₃ is found to supply remarkable buffering capacity on a global scale, from the polluted continents to the remote oceans.

In April 2021 the EGU Publications Committee launched the first author survey to routinely ask authors about their publishing experience in EGU journals, in order to learn more about how EGU and Copernicus can serve the scientific community with their publications. Over the last 6 months, 160 contact authors answered the survey representing about 10% of the papers published during this time. We are delighted about the positive feedback and thank all authors. Please read the full report.

Experiments at CLOUD show that in polluted environments new particle formation (NPF) is largely driven by the formation of sulfuric acid-base clusters, stabilized by amines, high ammonia concentrations or lower temperatures.

COVID-19 lockdown measures in spring 2020 led to cleaner air in central Europe. Densely populated areas benefitted mainly from largely reduced NO₂ concentrations, while rural areas experienced lower reductions in NO₂ but also lower ozone concentrations. Very low particulate matter (PM) concentrations in parts of Europe were not an effect of lockdown measures. Model simulations show that modified weather conditions are more significant for ozone and PM than severe traffic emission reductions.

Earth system models have a few persistent biases that impinge on our ability to make robust future regional predictions of precipitation. For the last fifteen years, there has been little to no improvement in these biases. This work presents an accurate representation of how dust absorbs radiation based upon its observed mineralogical composition and size distribution.

Secondary organic aerosol (SOA) is an important aspect of poor air quality for urban regions around the world, where a large fraction of the population lives. However, there is still large uncertainty in predicting SOA in urban regions.

The journal metrics were updated and the current numbers are available from the journal metrics overview.

The authors find that simulated stratospheric sulfate geoengineering could lead to warmer Eurasian winters alongside a drier Mediterranean and wetting to the north.

The authors find satellite observations of atmospheric composition generally reproduce variability in surface air pollution, so they use their long record to estimate air quality trends in major UK and Indian cities.

Cloud responses to aerosol are time-sensitive, but this development is rarely observed. This study uses isolated aerosol perturbations from ships to measure this development and shows that macrophysical (width, cloud fraction, detectability) and microphysical (droplet number) properties of ship tracks vary strongly with time since emission, background cloud and meteorological state.

A long-standing mystery of metal ions within E_s layers in the Earth's upper atmosphere is the marked seasonal dependence, with a summer maximum and a winter minimum. We report a large-scale winter-to-summer transport of metal ions from 6-year multi-satellite observations and worldwide ground-based stations. A global atmospheric circulation is responsible for the phenomenon. Our results emphasise the effect of this atmospheric circulation on the transport of composition in the upper atmosphere.

With great sadness, we have to announce that Paul J. Crutzen has passed away on 28 January 2021. Paul was not only an outstanding scientist and scholar, but a friend, colleague, and mentor for generations of atmospheric scientists. He had also been a long-time supporter of open-access publishing within EGU, where he played a key role in the foundation and establishment of its first OA journal, Atmospheric Chemistry and Physics, and served on its advisory board for many years. He will be sorely missed. Our thoughts are with his family. (Image credit: MPI for Chemistry)

Forest fires are an important source of reactive organic gases and aerosols to the atmosphere. The authors analyzed organic aerosols collected from an aircraft above a boreal forest fire and reported an increasing contribution from compounds containing oxygen, nitrogen, and sulfur as the plume aged, with sulfide and ring-bound nitrogen functionality.

Methane is an important energy source in Europe, but also a strong greenhouse gas. Previous research in the United States has shown that new equipment detects considerably more gas leaks than equipment currently used by local gas utilities. This also appears to be the case in two European cities, Hamburg in Germany and Utrecht in the Netherlands, researchers write today in Atmospheric Chemistry and Physics.

As of 1 November 2020 the direct settlement of article processing charges (APCs) between the ETH Zurich and Copernicus Publications will be valid for corresponding authors.

EGU is seeking scientists who want to gain experience in the realm of scientific publishing to pre-screen manuscripts submitted to the Union's new online platform.

We are proud to announce that ACP has just published its first ACP Letter. ACP Letters are short research articles that report particularly important results and major advances in a concise and engaging style. Read more.

The journal metrics were updated and the current numbers are available from the metrics box on the left-hand side.

Gothenburg University Library and Copernicus Publications have signed an agreement on the central billing of article processing charges (APCs) to facilitate the publication procedure for authors.

A new study shows that air pollutants from the smoke of fires from as far as Canada and the southeastern U.S. traveled hundreds of miles and several days to reach Connecticut and New York City, where it caused significant increases in pollution concentrations.

The Spanish National Research Council (Consejo Superior de Investigaciones Científicas, CSIC) will now provide a publication fund for their corresponding authors publishing in Copernicus' open-access journals.

Concentrations of methane, a greenhouse gas about 28 times more potent than carbon dioxide, have risen steadily in Earth's atmosphere since 2007. Although several potential explanations, including an increase in methane emissions from the tropics, could account for this upsurge, due to a lack of regional data scientists have been unable to pinpoint the source. Now a study published in ACP uses satellite data to determine that one-third of the global increase originates in Africa's tropics.

While Cristina Facchini and Rolf Sander have resigned from the executive committee, we are very happy to welcome Barbara Ervens as a new ACP executive editor.

As of 1 September 2019 the direct settlement of article processing charges (APCs) between the Helmholtz Association and Copernicus Publications will be valid for corresponding authors.

In the right conditions, airplane contrails can linger in the sky as contrail cirrus – ice clouds that can trap heat inside the Earth's atmosphere. A new study published in ACP has found that, due to air traffic activity, the climate impact of contrail cirrus will be even more significant in the future, tripling by 2050.

The journal metrics were updated and the current numbers are available from the metrics box on the left-hand side.

A video abstract is a short video statement providing authors with the opportunity to present background information about their findings and to showcase their research activities to a wider audience.

We are sad to announce that the Atmospheric Chemistry and Physics community has lost a highly valued member: Dr William Lahoz passed away in April 2019.

14 scientific institutions have joined the national opt-in consortium for the central payment processing of APCs for articles of all journals published by Copernicus Publications.

Iowa State University Library and Copernicus Publications have signed an agreement on the central billing of article processing charges (APCs) to facilitate the publication procedure for authors.

Copernicus Publications recently launched its full-text HTML workflow and optimized the ACP website for mobile devices. Thereby, the user experience is significantly enhanced when reading ACP articles.

To facilitate the publication procedure for authors from Helsinki University, Copernicus Publications and Helsinki University Library have signed an agreement on a central billing of article processing charges (APCs).

Data underpinning any research finding should be findable, accessible, interoperable, and reusable (FAIR) – not only for humans, but also for machines. Therefore, Copernicus Publications requests that such data are available upon publication of an article.

The latest Journal Citation Reports® have been published by Clarivate Analytics.

As of 1 May 2018 the centralized payment of article processing charges (APCs) with the Leibniz Association has been extended to 53 Leibniz Institutions participating in the Leibniz Association's Open Access Publishing Fund.

The ozone layer – which protects us from harmful ultraviolet radiation – is recovering at the poles, but unexpected decreases in part of the atmosphere may be preventing recovery at lower latitudes, new research has found. The new result, published today in ACP, finds that the bottom part of the ozone layer at more populated latitudes is not recovering.

After more than 16 years of serving the scientific community of Atmospheric Chemistry and Physics (ACP) with great dedication and success, William T. (Bill) Sturges has resigned from the executive committee that coordinates the ACP editorial board.

From 1 January 2018 Atmospheric Chemistry and Physics (ACP) will slightly increase the article processing charges.

"Ozone depletion is a well-known phenomenon and, thanks to the success of the Montreal Protocol, is widely perceived as a problem solved," says University of East Anglia's David Oram. But an international team of researchers, led by Oram, has now found an unexpected, growing danger to the ozone layer from substances not regulated by the treaty.

Authors from the Potsdam Institute for Climate Impact Research (PIK) will profit from a new institutional agreement with Copernicus Publications starting 23 August 2017. The agreement which is valid for the first author enables a direct settlement of article processing charges (APCs) between the PIK and the publisher.

The updated publication policy now is extended by the journal's open access statement, its archiving and indexing scheme, and explicit policies on corrections and retractions.

The general obligations for editors, referees, and authors have been revised to give advice for the appropriate handling of literature suggestions.

Clarivate Analytics has published the latest Journal Citation Reports®.

From 6 June onwards, all newly submitted articles, if accepted for publication, will be distributed under the Creative Commons Attribution 4.0 International License.

To make it as easy as possible for users without technical knowledge to cut and paste or click to share DOIs, CrossRef has changed the display and citation guidelines for DOIs from "doi:10.5194/abcd" to "https://doi.org/10.5194/abcd".

Since early 2016, Copernicus Publications has been enabling authors to connect their articles with underlying or related material such as research data, model code, or scientific videos. To enhance reproducibility it is now also possible to include International Geo Sample Numbers (IGSNs) as assets.

In 2016, the 17 EGU–Copernicus peer-reviewed open-access journals experienced significant growth. We published over 3300 final-revised papers, corresponding to some 53,500 pages, a growth of about 10% compared to the previous year. These papers were downloaded over 645,000 times.

Recently we have become aware of a case of scientific malpractice by an editor of two of our journals (SOIL and SE) who used the position as editor and reviewer to disproportionately promote citations to personal papers and associated journals. Please read the published editorial.

Authors from the Technical University Darmstadt will profit from a new institutional agreement with Copernicus Publications starting 1 January 2017. The agreement which is valid for corresponding authors enables a direct settlement of article processing charges (APCs) between the university and the publisher.

As of 1 January 2017 the direct settlement of article processing charges (APCs) between the Max Planck Digital Library and Copernicus Publications will be valid for corresponding authors.

Copernicus Publications has extended the article level metrics (ALMs) by showing the geographical distribution of views. This information is available for articles published after 3 August 2016.

Copernicus Publications and the Leibniz Association have agreed on a central billing of article processing charges (APCs) to facilitate the publication procedure for authors. So far three Leibniz institutes are participating in this agreement.

Copernicus Publications and the Technische Informationsbibliothek (TIB) in Hanover, Germany have signed an agreement on central billing of article processing charges.

We have summarized the upcoming changes to ACP by the end of the year.

In cooperation with the TIB|AV-Portal ACP authors can now add short, citable video abstracts and video supplements to their articles.

From January 2016 onwards, ACP will see changes to the way papers are archived and paid for.

A new study looking into short-lived pollutants reveals measures governments could implement to substantially improve air quality as well as fight climate change.

The Potsdam University Library and Copernicus Publications have signed an agreement on direct settlement of article processing charges (APCs).

We have updated our data policy: it now also refers to the Data Citation Principles and stresses the necessity of data availability.

Atmospheric Chemistry and Physics (ACP) has received the new DOAJ Seal which recognizes journals with an exceptionally high level of publishing standards and best practice.

Atmospheric Chemistry and Physics (ACP) has become a member of the Committee on Publication Ethics (COPE) and thereby subscribes to the principles of COPE.

The Copernicus Medal 2015 was awarded to Professor Ulrich Pöschl for his outstanding and pioneering work as well as his contributions to open science.

The ACP website has been given a new look, and the navigation has been adjusted. Further details:

In order to further promote open access, the TU Delft Library has transferred a budget to Copernicus to be used by its scientists in 2015.

Copernicus Publications and the University Library of the Technical University Munich (TUM) have agreed on central billing of article processing charges.

From 01 January 2015 Atmospheric Chemistry and Physics (ACP) will slightly increase the article processing charges.

Atmospheric Chemistry and Physics (ACP) has started an XML-first workflow and will provide all new articles in full-text XML from now on.

The ETH-Bibliothek (the central university library for ETH Zurich) and Copernicus Publications have signed an agreement on central billing of article processing charges.

The University of Bremen has now signed an agreement with Copernicus Publications about the central billing of article processing charges.

Article level metrics (ALMs) comprise a set of easy-to-understand real-time impact indicators that track how an article is read, discussed, or cited.

ACP has introduced transparent post-discussion review.

ACP has implemented publication ethics in order to guarantee high scientific and ethical standards.

ACP has just published its new data policy.

An anniversary publication celebrating 10 Years of Interactive Open Access Publishing.

We are glad to announce a special issue dedicated to scientific studies of the volcanic eruption of Eyjafjallajökull, the evolution and properties of the resulting plume, and their consequences.

The European Geosciences Union has published a position statement to clarify the definition and standing of discussion papers published in the interactive open access journals.

The ACP editors welcome two new sister journals with complementary aims and scope.

According to the latest Journal Citation Report of the Institute of Scientific Information (ISI-JCR 2007), the impact factor of Atmospheric Chemistry and Physics (ACP) has increased again.

The journal impact factor of Atmospheric Chemistry and Physics (ACP) is the highest of all journals in the category "Meteorology & Atmospheric Sciences".