World Meteorological Day

Yes, today is World Climate Day! The moderators of this forum should create some environmental-themed content for this day. Why is the air quality getting worse these days? What are the main reasons for the current poor air quality?

World Meteorology Day 2009: Weather, Climate and the Air We Breathe: Protecting Human Health and the Environment – Message by M. Jarraud, Secretary-General of the World Meteorological Organization. The World Meteorological Organization (WMO) and the international meteorological community celebrate World Meteorology Day every year to commemorate the entry into force of the WMO Convention on March 23, 1950, 30 days after the 30th instrument of ratification or accession was deposited with the organization. From that day on, the WMO assumed the responsibilities of the former International Meteorological Organization (IMO). The IMO was established at the First International Meteorological Congress (September 1873, Vienna) with the aim of promoting international cooperation in meteorology, including coordinated observations and the standardization of meteorological instruments. One year after the reorganization, in 1951, WMO became a specialized agency of the United Nations system. Currently, the WMO has 188 ** and regional members, and its responsibilities have also expanded to water and environmental issues. Given that it has become a tradition for the WMO to celebrate World Meteorology Day each year around a relevant theme, the WMO Executive Council decided that the theme for 2009 would be “Weather, climate and the air we breathe”. At this time, this theme is particularly appropriate, as the international community is striving to achieve the United Nations Millennium Development Goals, especially in terms of human health, food, water security, and poverty reduction, as well as improving the capacity to prevent and mitigate natural disasters. 90% of such disasters are directly related to weather, climate, and water-related events, and thus fall within the scope of WMO’s responsibilities. Furthermore, scientists and medical professionals are increasingly aware of the important relationship between weather, climate, the composition of the air we breathe, and its impact on human health. For many centuries, in order to live in harmony with climate and environmental conditions, humanity has sought to adapt properly to the effects of weather and climate by adjusting its dwellings, food production, energy supply, and lifestyle. However, over the past few decades, population growth, increased energy use, and industrial development have led to the emission of various gases and particulates, which have been able to and indeed have affected human health. Therefore, the continuous decline in air quality has exacerbated cases of asthma, heart disease, and lung cancer, as well as worsened many other medical conditions, and even become the root cause of the aforementioned situation. Furthermore, since plants, crops, and ecosystems are severely affected by air pollution, it has an impact on the global economy, food and water security, and sustainable development. It is worth recalling that Hippocrates (around 460–377 BC), regarded as the \"father of medicine,\" opposed superstition, advocated scientific observation, classified diseases, and established moral and professional standards that remain valid to this day. In particular, his work written in the 5th century BC, \"On Air, Water, and Place,\" considered the impact of climate, water supply, and geographical regions on human health, and compared the geophysical conditions in Europe and Asia where humans lived. In the time of Hippocrates, it was generally believed that there were only four elements: earth, air, fire, and water, with cold, dryness, heat, and humidity being their corresponding characteristics. If these elements are present in appropriate amounts in the human body and in the right locations, they contribute to good health. If balance is lacking, where can health be found? It is well known today that trace gases and particulates in the air have a significant impact on climate, weather, and air quality. Currently, meteorologists, climatologists, and atmospheric chemists are working together to provide medical professionals and environmental scientists with predictions and analyses regarding the distribution, concentrations, and transport patterns of various gases and particles in the atmosphere, thereby contributing to mitigating the impacts on weather, climate, and the quality of the air we breathe. As early as the 1950s, the WMO took the lead in coordinating the observation and analysis of atmospheric composition. Currently, a global network consisting of ground-based observation stations, remote sensing stations, balloon radiosondes, aircraft, and satellites enables the regular collection of data on greenhouse gases, aerosols, and ozone, as well as traditional meteorological and hydrological parameters. This has already helped people understand the constantly changing composition of the atmosphere, and it has laid a scientific foundation for our current understanding of the impact of weather and climate on air quality, as well as the mutual influences between atmospheric composition and weather and climate. Many of the WMO’s pioneering examples of activities can be traced back to scientific research initiatives launched in the context of the International Polar and Geophysical Year, which required the efforts of the **Meteorological and Hydrological Services (NMHS)** of WMO members, as well as cooperation with other international organizations. In response, the WMO has actively participated in various international efforts aimed at assessing the changing atmosphere from the perspective of air pollutants, including those directly generated by industrial, urban, and motor vehicle combustion of fossil fuels, such as ground-level ozone, smog, particulate matter, sulfur dioxide, and carbon monoxide. The WMO was the founding organization of three important international conventions related to atmospheric composition, namely: the Convention on Long-Range Transboundary Air Pollution of the United Nations Economic Commission for Europe (1979), the Vienna Convention for the Protection of the Ozone Layer (1985), and the United Nations Framework Convention on Climate Change (1994). Currently, to take global action, the WMO continues to support the aforementioned vital international mechanisms. Currently, we realize that many air pollutants resulting from the Industrial Revolution are also responsible for other climate changes; based on astronomical and geophysical influences alone, we have already predicted that these changes exceed the range of natural variability. The **Intergovernmental Panel on Climate Change (IPCC)**, jointly established by the WMO, published its Fourth Assessment Report and was awarded the prestigious Nobel Peace Prize in 2007. The report concludes that climate change is undeniable and is likely caused by increased human greenhouse gas emissions. The IPCC further predicts that, due to changing climates, the frequency and intensity of floods, droughts, and other extreme weather and climate events will increase, particularly heatwaves, which can have adverse effects on human health, exacerbate pollution incidents, and fuel wildfires. Wind, rain, snow, sunlight, and temperature have varying effects on the transport and retention of air pollutants. Heat generated by cities traps pollutants, while rain and snow carry pollutants from the atmosphere to land and oceans. Scientists can use weather models to assess and predict the distribution of air pollution. Therefore, timely, appropriate, and accurate air quality forecasts help protect people’s lives and property, and they also serve as a complement to the more traditional weather forecasting. Although regional air quality forecasting has seen significant improvements over the past 30 years, providing such forecasts to local stakeholders in a timely manner remains a challenge. However, an increasing number of NMHSs are now participating in the issuance of air quality forecasts, and many of them also provide various air quality indices and advice, such as through a colored coding system. Given the varying ways in which consultations are issued across regions, WMO promotes training to maximize the effectiveness of such products and their social benefits. Such forecasting products have never been so necessary before. The World Health Organization estimates that an average of 2 million minors die each year due to air pollution. Even when the concentrations of ozone, particulate matter, and related pollutants are relatively low, they can still have subtle effects on respiratory and heart health, especially in developing countries. Therefore, air quality forecasts serve as an important early warning tool that helps to mitigate the harms associated with air pollutants. With the development and expansion of metropolises, urban pollution is affecting an increasing number of people around the world. Nearly half of the world’s population lives in large cities, many of which lack any form of air quality monitoring, especially in developing countries. Therefore, raising funds and formulating appropriate policies to monitor and address these **air pollution issues is an increasingly serious challenge. Currently, the WMO’s Global Atmosphere Watch and World Weather Research Programme are actively expanding the range of air quality services provided by the NMHS of WMO member states. To improve the capacity for forecasting air pollution and mitigating its impacts, some **projects have been launched. In addition to coordinating air quality forecasts, the WMO is also promoting research on air pollution. Suspended particulates (or aerosols) are crucial factors in determining the heat absorption or reflection by the surface, clouds, and atmosphere, as well as in the formation of these clouds and precipitation. Although rainfall can wash away aerosols in the lower atmosphere within a few days, some particulate matter can remain in drier air masses and the upper atmosphere for longer periods, thereby having varying degrees of impact. Therefore, aerosol research has become an important field of study and will constitute a major part of the next generation of climate prediction and weather forecasting models. Dust content is also crucial for air quality. Dust can reduce visibility, harm crops, and affect the local climate. An important goal of the WMO Dust Storm Warning, Assessment and Advisory System is to address the specific challenges posed by dust storms; it facilitates the generation of relevant forecasts as well as the study and assessment of the impacts of dust storms. Some WMO member states and partner organizations are currently working on research and operational forecasting for such harmful weather phenomena, which particularly affect northern Africa, Asia, and North America. In addition, the NMHS of WMO members and some of WMO’s partner organizations play a key role in monitoring and responding to environmental emergencies. In such emergencies (such as industrial chemical leaks, volcanic eruptions, air-borne diseases, or nuclear power plant accidents), harmful substances can be released; during these times, meteorologists are able to predict the spread and dispersion of these harmful substances after they are released. To this end, through close cooperation with the World Health Organization, the International Atomic Energy Agency, the International Civil Aviation Organization, and other partners, WMO’s emergency response activities plan helps to utilize its network of regional specialized meteorological centers for the numerical simulation of air-borne pollutants. Through various air quality-related programs, the WMO and its member NMHSs raise awareness among policymakers and the public about the close relationship between weather, climate, and the air we breathe by providing them with the most relevant and authoritative information. This is a collaborative effort that requires the joint cooperation of many organizations and industries. The Third World Climate Conference (WCC-3) will be held in Geneva from August 31 to September 4 this year, and against the backdrop of this conference, the importance of such cooperation will become evident. At this important event, NMHS will continue to play a key role in protecting human health and the environment. I am firmly convinced that the theme for World Meteorology Day 2009 will further contribute to maximizing the participation of WMO members and partners. I would like to take this opportunity to extend my sincere congratulations to them.