Climate change and air pollution have negative impacts on several aspects of human activities, especially on health and economies. Environment-related hazards – extreme weather events, failure of climate- change mitigation and adaptation, natural and human- made disasters, water crises, biodiversity loss and ecosystem collapse – have ranked as the top global risks for three years running in the World Economic Forum’s Global Risk Perception Survey. In the 2019 Survey, these risks accounted for three of the five most likely to occur and four of the five risks with the highest potential impacts. It is more urgent than ever, that WMO provides, as per its mandate, the best available weather, climate, water and environmental science and expertise as the foundation for mitigating these risks as well as for sustainable and resilient development.
Long-term atmospheric measurements are key to delivering on this mandate. The past decade of intensive research on atmospheric composition, health and climate has closed many scientific gaps. It is now possible to develop information products adapted to a variety of policy-relevant applications such as the identification of pollutant emission sources, production of reliable air quality forecasts and evaluations of the effectiveness of emission reduction policies.
In order to meet the needs of user communities working on the diverse impacts of atmospheric composition on climate, human health, food security and ecosystems, the development of modelling tools has to be tailored to specific applications. Models need to be compared with measured atmospheric composition to be improved and validated. Observational data on the atmosphere is also needed for model initiation and data assimilation. Therefore, the availability and sustainability of data of known quality in terms of precision, accuracy and representation is of paramount importance to support improvement of modelling tools and applications.Yet, important observational data are missing, especially in developing countries.
Relevance in achieving global goals
Figure 1: Global distribution of GAW stations from the GAW Station Information System (GAWSIS). GAWSIS is the official catalogue of GAW stations and Contributing networks. It provides the GAW community and other interested people with an up-to-date, searchable data base of metadata related to atmospheric composition measurements.
Parties to the Paris Agreement on climate change have agreed to work towards limiting the global mean temperature rise to well below 2 °C above pre- industrial levels. Changing atmospheric composition is an important driver of climate change. For instance, on the global scale, changes in concentrations of long-lived greenhouse gases (GHGs), such as carbon dioxide, have contributed to global warming, whereas, on the regional scale, compounds with shorter lifetimes enhance or slightly reduce global warming.
Atmospheric pollutants are also responsible for poor air quality, which causes an estimated seven million premature deaths every year (World Health Organization, 2016). Even small amounts of air pollutants can have serious impacts on human health. Fine particles are particularly harmful due to their ability to penetrate deep into lungs and blood streams. At the first World Health Organization (WHO) Global Conference on Air Pollution and Health in 2018, participants agreed on the aspirational goal of reducing the number of premature deaths from air pollution by two thirds by 2030. Capability to predict the evolution of atmospheric composition and its impacts on human and ecosystem health starts with quantifying emissions, as well as the transport, transformation and deposition of gases and particulate matter, at the relevant scale for policymaking. At the event, WMO committed to improving the evidence of air pollution levels and to providing tools for forecasting and preventing acute episodes of air pollution.
A decrease in atmospheric pollutant concentrations is the ultimate indicator of a successful policy to reduce emissions, as demonstrated by the Convention on Long-Range Transboundary Air Pollution (LRTAP). To guide such policies, the observational gap in developing countries needs to be bridged.
Atmospheric research infrastructure
In situ atmospheric observations are complex and can involve multiple partners. Some are organized in measurement networks, active at regional or global scales, while others work almost independently. The WMO Global Atmosphere Watch (GAW) is a unique coordinating body for many of these networks, promoting coherent measurement protocols and standards, data interoperability, and unique access to information and data. Although still far from the full global level of standardization and interoperability, it is evident that substantial progress has been made in the last decade. GAW coordination has helped to harmonize measurement techniques and observational quality among networks worldwide, and to process and provide access to data, implemented by different organizations and programmes.
Surface-based observations are complemented by airborne and space-based observations that help to characterize the upper troposphere and lower stratosphere. Space-based observations provide global coverage for many atmospheric parameters. Nevertheless, they are not sufficient to provide information with the required degree of spatial and temporal resolution needed for many applications, including those for scientific research, business development and policymaking. While surface-based observations remain indispensable for monitoring atmospheric composition and are also required for the evaluation of satellite-derived retrievals, the capacity is lacking in many parts of the developing world.
Currently, existing in situ observations are mainly based on infrastructure operated at the national level or by academic institutions at a smaller scale. They are sustained in only a limited number of regions in the world, resulting in an inadequate distribution. While the current situation in Europe has improved thanks to the establishment of long-term research infrastructures such as ICOS, IAGOS or ACTRIS, global coverage is lacking, with substantial gaps in Africa, Latin America and large parts of Asia (see Figure 1).
Although this may be due to difficulties making the data accessible through World Data Centres, for many areas of the world, the gaps are related to missing observational infrastructure, particularly in emerging economies. Reliable detection of trends in atmospheric chemical composition requires long (>10 years), high- quality records. Despite many initiatives, only a few stations in under-represented regions have managed to maintain operations for observing composition changes over more than a decade (for example, see the box on Chacaltaya station). Long-term funding is required for such long-term measurements. This represents a continued commitment, which is difficult to achieve for many economies.
Key factors for sustainable observations
More than 50 scientists shared their experiences in implementing the GAW strategy around the world at a recent event on the Sustainability of Atmospheric Observations in Emerging Economies. The following series of recommendations were derived from the presentations and follow-up discussions.
Raising awareness and stimulating demand for observations and information on climate and air quality – of the kind provided by GAW at the user level – are important. GAW observations are more sustainable when embedded in an ongoing national programme. Establishing climate platforms at the national level that would link with potential users on a sustainable basis would be beneficial. These may include policy stakeholders, ranging from national to municipal level, representatives from industry and land managers.
Dialogue among stakeholders and representatives from research would help in building awareness at the user level and provide a platform to articulate the needs and demands of users in terms of the observations and information on climate and air quality that are required. Awareness may initially arise from the demand for specific information or application of high interest to a country. Providing information in response to this specific demand can stimulate dialogue and extend the interest and support for other services based on atmospheric observations − particularly in developing countries, where such considerations have been limited.
Holistic partnerships should be catalysed. Participation in GAW activities is often not restricted to a single partner (such as a National Meteorological and Hydrological Service (NMHS)), and much of the success of GAW is due to its enlargement to include relevant academic research communities. The academic community in a country can be a powerful partner, providing high-quality data, advance technology and advise on the scientific context of atmospheric observations. Moreover, it can articulate the importance of GAW observations for environmental services and motivate national support by raising awareness at governmental agencies.
Examples of successful implementation are also linked to regional approaches. Focused engagement in one region rather than in a single country may be more purposeful in relation to air pollution monitoring. WMO plays a key role in connecting countries regionally, ensuring that the various national initiatives in a particular region mutually enrich each other, and make full use of established networks and contacts.
In addition, international collaboration is crucial to success. A sound information and knowledge base derived from high-quality climate data is essential to tackle the challenges related to climate variability and change. Systematic long-term monitoring of the climate system is a fundamental prerequisite to understand its change and the resulting consequences, and a key factor in decision-making at all levels. Climate data and information also have direct relevance to policymaking in areas such as water management, agriculture, disaster risk reduction, health and energy. Long-term observations of GHGs and aerosol properties, all considered Essential Climate Variables (ECVs), are indispensable.
There was a clear view among participants, especially those from emerging economies, that WMO must continue to advocate for national stakeholders to support ECV monitoring from ground-based networks as part of a more global Earth Observation System. WMO support was requested for explaining the local benefits that monitoring atmospheric composition changes will bring to a country, specifically those related to socioeconomic impacts in the short and longer terms.
The investment required for operating an observational platform is substantial and does not end after equipment installation. Development of autonomous samplers and analysers, capacity-building and relocation of observation capacity for specific species (such as ozone) would be among priority actions. Existing international cooperation, such as that with established networks and data centres, should be sustained and improved. It is also important that the international community supports countries that do not have the capabilities or the capacities to install and maintain the observational infrastructure, and to perform the relevant measurements, analyses and quality control. Close collaboration among different partners such as NMHSs, environmental protection agencies, universities and research institutes will be key to success.
Uncoordinated investments have led to a fragmented flow of projects funded by development partners, often resulting in a patchwork of observation infrastructure and technologies that are impossible for NMHSs to sustain (WMO, 2019, Resolution 74, Annex I).To address WMO Strategic Objective 4.3, which calls for closing the capacity gap on weather, climate, hydrological and related environmental services through effective partnerships (WMO, 2019, Resolution 1), the WMO Country Support Initiative (CSI) was established through Resolution 74 (WMO, 2019).The CSI will provide advisory services aimed at increasing effectiveness of investments in such services.
Participants arriving for their GAWTEC training (left) and participants during the GAWTEC 34th training session which took place in October 2018.
Continued integrated GAW training and capacity- building was unanimously called for by participants. Capacity-building should not be restricted to the technical dimension for maintaining operation at monitoring stations, but also include a wider level, to raise expertise in relation to science and technologies, science management, adaptation strategies, etc. It was seen as a prerequisite for partners in developing countries with emerging economies to be actively involved in seeking funding on the national or regional levels, and through multilateral development organizations and banks, engaged in climate information and services. Participation of women should be encouraged in general, and especially in training and capacity-building activities. An integrated approach would also target the affected communities and includes empowering local people to make effective use of the environmental information and services provided.
Capacity development is one of the strategic priorities of the WMO financial period 2020–2023. Within WMO, the GAW Training and Education Centre (GAWTEC) is the only regular training facility for atmospheric composition observations. Since the first GAWTEC training course in 2001, more than 400 trainees from 76 different countries have been trained at the Environmental Research Station Schneefernerhaus. Current capacity-building activities also include support for early career researchers to attend scientific conferences and training schools. In 2019, a new course, Seamless Prediction of Air Pollution: From Regional to Urban, was offered as part of a new Africa Initiative.This was developped in partnership with a recent GAW activity on Air Quality and Meteorological Predictions and Forecasting Improvements for Africa (PREFIA).
Tailored implementation is the most sustainable approach. A distributed set of research sites that take the best possible advantage of the existing infrastructure in other programmes would be most cost-effective. Selection of the best location, measured variables and operating models is often based on an opportunity basis rather than a thorough scientific evaluation.
It is critical that new observational sites are selected and implemented to fill gaps in the global observing system.This can employ similar mechanisms as those that will be developed for meteorological observations in the Global Basic Observing Network (GBON), which represents a new approach where the basic surface- based observing network is designed, defined and monitored at the global level.
Beyond the atmospheric component discussed here, sites for integrated measurements should be identified for a global Earth observatory of 1 000 or more well- equipped ground stations that track environments and key ecosystems comprehensively and continuously (Kulmala, 2018). Priority sites for atmospheric and integrated Earth system observatories should be identified by expert teams involving local scientists and organizations (Kulmala, 2018).
Providing generalized suggestions that recommend a particular strategy is difficult as various options may be developed and evaluated based on national laws, contexts and circumstances, and local communities. For example, in the European Union, the research infrastructure is based on a common economic and legal framework. Accounting for country- and region- specific implementation, WMO is seen as a key actor to help develop clear communication and outreach strategies to ensure effective sharing of progress, lessons learned, experience and knowledge across all stakeholders and partners.
Role of research funding
Typical research funding cycles are much shorter than the timescales relevant to study climate change or to detect changes in pollutant concentrations resulting from the implementation of air quality regulations. Therefore, the research infrastructure required to generate time series long enough to analyse trends cannot be maintained through current research funding calls. A different type of mechanism specifically designed to address long-term changes with projects that have a longer funding period is necessary.
Project-based funding for initial research infrastructure implies that a longer-term plan needs to be developed to ensure continued operational observations beyond the funding cycle. For example, the European Research Infrastructure ACTRIS, including its quality assurance and quality control protocols, has been initiated through research funding. Established research sites with core measurement capabilities and long- term knowledge about regional photochemistry, meteorology, ecosystem properties and biosphere– atmosphere exchange processes are a critical resource for making and interpreting new measurements.
Beyond the scientific interest in trends, potential synergies – and funding – exist with other agencies that require information on the state of the atmosphere based on long-term measurements.
Supporting atmospheric observations in emerging economies
It is vital to work towards global coverage of ground- based atmospheric observations to provide high-quality information on climate and air quality, particularly by addressing gaps in the observational networks of developing countries. Existing observational sites should be taken into account in order to optimize costs, while support should be provided to those struggling to maintain observations. For selection of new observational sites, a thorough scientific evaluation of the best location, measured variables and operating model to fill the gaps is required, rather than basing new sites purely on emerging opportunities.
Large-scale coordinated effort and commitment by multiple partners – including NMHSs, environmental protection agencies, the research community and multiple funding agencies – are essential to ensure support of observations for climate and air quality. Strong local and national support is key to success for long-term commitment in a country.
Expert teams should involve local scientists and organizations to develop a tailored implementation approach that takes local circumstances into account. Support of the international community is crucial for capacity-building and implementation of standardized quality assurance and quality control protocols. Advice can be obtained based on lessons learned from past experiences.
Chacaltaya – the highest GAW station in the world: a story of horizontal collaboration
In less than a decade, a site that formerly had a focus on cosmic ray research has become one of the most active observation stations in the GAW network. At an elevation of more than 5 000 metres, it is a unique place for hosting atmospheric science experiments and is now an attraction for researchers worldwide. In June 2018, an international group of scientists descended from the Mount Chacaltaya GAW station (16°21S, 68°07 W, 5 240 m above sea level), ending a six-month intensive campaign to study processes driving the formation of new atmospheric particles. The experiment that gathered scientists from eleven different countries and three continents occurred almost six years after the station officially opened in 2012 as a GAW station.
The Laboratory for Atmospheric Physics (LFA) of the University Mayor de San Andres in La Paz (UMSA), Plurinational State of Bolivia, was established in 1995 with a focus mainly on ultraviolet radiation and total ozone. These topics remain important subjects in a country where the levels of ultraviolet radiation are among the highest in the populated world. It marked the beginning of Bolivia's systematic atmospheric research.
The increasing impacts of climate change on tropical Andean environments made evident the need to broaden the subjects of atmospheric research performed by the Laboratory. In 2009, researchers from France and Italy approached LFA simultaneously but independently with a common interest in the feasibility of performing atmospheric measurements at Mount Chacaltaya. The site had been used for several decades for cosmic ray research (the pi meson was discovered there and contributed to the award of the 1950 Nobel Prize in Physics), but its high altitude and strategic location within the South American continent was also ideal for monitoring atmospheric composition. The Chacaltaya project started under UMSA leadership, with the key idea of making a long-term capital and human investment to create and sustain a research platform equipped with baseline instruments committed to long-term observations.
Original investments for rehabilitation of the station were made by UMSA, which also offered two engineering positions in the Department of Physics to support scientific and technical operations. Partners in Europe and the United States of America donated scientific instruments and engaged in training activities for UMSA personnel (students, engineers and scientists). In December 2011, the new consortium of scientists switched on their instruments, thus establishing the station for monitoring reactive gas and GHG concentrations as well as physical and chemical properties of particulate matter reaching this high-altitude location.
The site has been working continuously since then, with very few data gaps, providing the scientific community with open access to high-quality data, resulting in several scientific papers in international journals. Local Bolivian personnel in mainly European international schools have gained valuable theoretical and practical skills in atmospheric science and instrumentation. Many Bolivian undergraduate and graduate students, many of them women, have also received training in atmospheric sciences. Three former UMSA staff members and one permanent staff member of LFA are currently pursuing their graduate and doctoral studies in France, Germany and Finland.
The first key to success was the recognition of host university UMSA and its Institute for Physics Research to recognize that the Chacaltaya project was strategic to its development and visibility. UMSA has maintained long-term financial support to keep the infrastructure, which runs in a harsh, high-altitude environment. The second key factor was the role of foreign research institutions. The French Institute for Research and Development, also established in the Plurinational State of Bolivia, provided essential scientific, financial, administrative and logistical support to Chacaltaya station operations. Other research institutions and universities in Europe and in the United States also provided additional support, which was also critical to the success of the operation.
Although economic and scientific impacts are already measurable, a full economic model that would ensure sustainability of the Chacaltaya research platform is yet to be defined. Opportunities exist such as integration of Chacaltaya into European Research Infrastructure initiatives such as ICOS or ACTRIS but commitment to long-term operations is never trivial even in a successful capacity-building story such as Chacaltaya.
Kulmala, M., 2018: Build a global Earth observatory. Nature, 553(7686):21–23.
World Economic Forum, 2019:The Global Risks Report 2019. Geneva.
World Health Organization, 2016: Global Health Observatory (GHO) data, https://www.who.int/gho/ phe/air_pollution_mortality/en/.
World Meteorological Organization, 2019: World Meteorological Congress: Abridged Final Report of the Eighteenth Session (WMO-No. 1236). Geneva.
Paolo Laj, Université Grenoble Alpes, France, and University of Helsinki, Finland
Marcos Andrade, Universidad Mayor de San Andres, Plurinational State of Bolivia, and University of Maryland, USA
Ranjeet Sokhi, University of Hertfordshire, UK
Claudia Volosciuk, WMO Secretariat
Oksana Tarasova, WMO Secretarit