The long-known negative effects of air pollution on the lungs and cardiovascular system are just the tip of the iceberg. More and more scientific studies are pointing out that substances and particles (viac…)

Document stresses the need for better monitoring of climate change in the middle and upper atmosphere. Anthropogenic greenhouse gas emissions have a significant impact on the middle and upper atmosphere, causing cooling, shrinkage, and affecting the structure of the atmosphere.This shrinkage affects the lifespan of objects in low Earth orbit, radio communications and GPS signals, as well as the altitude of meteoroids entering the atmosphere.

Key points:

• Further research is needed on the impact of climate change and anthropogenic emissions on the middle and upper atmosphere.
• Lack of observational skills prevents better understanding and monitoring of long-term trends.
• The accumulation of space debris is a problem that anthropogenic emissions are exacerbating.

Impacts of climate change on the upper atmosphere:

• Changes in the thickness of the layers of the atmosphere, including the expansion of the troposphere.
• Changes in energy modes and baroclinicity of the middle atmosphere.
• Cooling and shrinkage of the stratosphere, mesosphere and thermosphere.
• Decrease in thermosphere density.
• The complex role of ozone, where its concentration can be affected by falling temperatures, and changes in ozone concentration affect temperature trends.
• Changes in the Brewer-Dobson circulation (BDC) are related to the expansion of the troposphere and the contraction of the stratosphere.

Long-term changes in the middle and upper atmosphere have practical consequences, such as impact on global positioning systems (GPS) and radio communications. Increasing water vapor and ice crystal content in the mesosphere causes a positive trend in polar mesospheric summer echoes, which can interfere with radar and military operations. Decreasing atmospheric density may lead to greater penetration of meteoroids into the atmosphere.

The most significant problem caused by climate change in the middle and upper atmosphere is the impact on space debris.. Increasing cooling and shrinkage leads to a decrease in density in the thermosphere, which prolongs the lifetime of satellites in orbit and increases the risk of collisions. Collisions can cause disruption to global satellite services and produce additional debris, which can lead to Kessler syndrome, a cascading effect of collisions.

Observation and data limitations:

• Lack of knowledge about the connections between atmospheric layers and how climate changes in the middle and upper atmosphere affect the troposphere.
• Missing information on global long-term changes in the upper atmosphere, such as composition, dynamical variables, winds, and gravity waves.
• The loss of some satellite missions designed to monitor this region of the atmosphere, such as ICON, AIM, and the potential loss of AURA and TIMED.
• Many existing satellite missions are already beyond their expected lifetimes, and new missions may not allow for long-term and homogeneous measurements.
• Lack of missions to monitor dynamic variables in the upper atmosphere.

Addressing knowledge gaps and challenges:

• The need to expand and maintain existing observational capabilities to ensure long-term and homogeneous data.
• Focus on stability, calibration, and implementation of cross-calibration within the observation system.
• Design new observations specifically to measure trends in temperature, density, and other parameters.
• Support the development of geospatial data records (GDRs) to determine variability and changes in geospace.
• Improved monitoring can contribute to reducing uncertainty in estimates of aerosol loading from volcanic eruptions and allow monitoring of the testing or deployment of climate intervention techniques.
• Improved monitoring would provide a better understanding of polar mesospheric clouds and their relationship to CH4, increasing water vapor concentrations, and decreasing mesospheric temperatures.
• It is essential to better predict the potential impacts on the future environment of space debris in low Earth orbit (LEO) and to predict the impacts on the probability of Kessler syndrome.
• Satellites release various materials directly into the middle and upper atmosphere during reentry, which can affect O3 concentrations and temperature trends.
• The planned increase in the number of satellites in low Earth orbit could cause up to half of stratospheric sulfuric acid particles to contain metals from reentry.

The document emphasizes that Data shortages and declining observational capabilities pose a serious challenge to understanding and monitoring changes in the middle and upper atmosphere., which has potentially far-reaching implications for space activities, communications and future climate change. Spring

The paper was published in AGU Advances

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Key Terms – Glossary

• Baroclinicity: A state of the atmosphere in which isobars (lines of equal pressure) are not parallel to isotherms (lines of equal temperature).
• Thermosphere: The layer of the atmosphere above the mesosphere, characterized by increasing temperature with height.
• Ionosphere: A layer of the atmosphere that contains ions and free electrons.
• Gravitational waves: Waves in the atmosphere that transfer energy and momentum.
• Space debris: Artificially created objects in Earth orbit that are no longer functional.
• Stratopause: The boundary between the stratosphere and the mesosphere.
• Reanalysis: Combining model and observational data to create a comprehensive picture of the state of the atmosphere.
• Climate intervention: the deliberate and large-scale manipulation of the Earth's climate system to mitigate the effects of climate change.
• Anthropogenic greenhouse gas (GHG) emissions: Greenhouse gas emissions from human activity.
• Middle and upper atmosphere: The part of the atmosphere above the troposphere, including the stratosphere, mesosphere, thermosphere, and ionosphere.
• Thermal shrinkage: Reduction in the volume of the atmosphere due to cooling.
• Stratopause: The boundary between the stratosphere and the mesosphere.
• Ionosphere: A layer of the atmosphere that contains ions and free electrons.
• Thermosphere density: The number of particles in the thermosphere.
• Low Earth Orbit (LEO): Orbits that are relatively close to Earth (usually less than 2000 km above the surface).
• Space debris: Artificially created objects in Earth orbit that are no longer functional.
• Global Positioning Systems (GPS): Satellite navigation systems.
• Scintillation: Rapid changes in the intensity of radio signals caused by ionospheric irregularities.
• Maximum usable frequencies: The highest radio wave frequencies that can be used for communication between two points through the ionosphere.
• Brewer-Dobson circulation (BDC): Global air circulation in the stratosphere.
• Quasi-Biennial Oscillation (QBO): Periodic change in wind direction in the stratosphere.
• Gravitational waves: Waves in the atmosphere that transfer energy and momentum.
• Polar mesospheric summer echoes: Radio reflections from ice crystals in the mesosphere during polar summer.
• Kessler syndrome: A theoretical scenario in which the density of space debris in low Earth orbit would become so high that collisions between objects would create more debris, leading to more collisions, and so on.
• Reanalysis: Combining model and observational data to create a comprehensive picture of the state of the atmosphere.
• Geospatial data records (GDR): Time series of measurements with sufficient length, consistency, and continuity to determine variability and changes in geospace.
• Ozone depleting substances: substances that damage the ozone layer.
• Climate intervention: the deliberate and large-scale manipulation of the Earth's climate system to mitigate the effects of climate change.

Document addresses the growing impact of environmental risks on the European Union's crisis management. It points out that extreme weather events and environmental degradation undermine stability, increase migration and threaten food security. Despite the EU's recognition of these risks, the integration of environmental aspects into security policy has been slow due to unclear mandates and a lack of expertise. The document highlights the need for better anticipation and preparedness and suggests strategic ways to integrate environmental issues into EU monitoring, analysis and early warning systems. It also points out that proactively addressing environmental risks is more effective than reactive measures. Spring

Remember when 2°C of global warming was a doomsday scenario? Well, now we're looking at something much worse. From the fish on your plate to the weather outside your window, everything is about to change. (viac…)

Climate Policy Explorer provides data accessible to policymakers and anyone interested in climate policies around the world. The dashboard allows for sector-by-sector overviews and country-by-country data visualization. This tool helps identify success stories and ultimately design better policies.

EEA assessment , which assesses progress towards the objectives set out in the so-called 8th Environmental Action Programme (EAP) It sets out the framework for EU environmental policy until 2030. Progress is assessed against a set of 28 headline indicators and corresponding targets in areas that include climate neutrality, a resource-efficient economy, reversing biodiversity loss and reducing pollution.

The report found that the EU is not yet on track to meet many of the targets, with overall progress limited compared to the last report in 2023. This is evidenced by the need for decisive measures to ensure their fulfilment by 2030 by fully implementing the policies under the European Green Deal.

Study examines the resilience of the Atlantic Meridional Oscillating Circulation (AMOC) to climate extremes and greenhouse gases. The study uses 34 climate models (viac…)

Welcome to the NOAA Carbon Cycle Greenhouse Gases group information website! The central site for global greenhouse gas monitoring and is in charge of operating the global air sampling network that continues to monitor the air we breathe.

February 23 425.09 ppm

Safe concentration: 350 ppm

ppm – the number of particles of carbon dioxide per million particles of air.

More on gml.noaa.gov

Aviation is a significant contributor to global CO2 emissions and climate change. As passenger numbers grow, aviation's environmental impact is expected to increase. (viac…)

This document represents first study of methane emissions from glacial rivers in Spitsbergen and suggests that summer methane flushing from beneath the approximately 1,400 continental glaciers in Spitsbergen may represent a significant seasonal source of emissions. (viac…)

Global water gaps are widening due to climate warming, leading to worrying water shortages in many regions of the world. (viac…)

Documents provides a preliminary estimate of the climate change mitigation potential through the Common Agricultural Policy (CAP) Strategic Plans in 18 EU Member States (EU-18) over the period 2018-2020. (viac…)

The European Environment Agency (EEA) has published its second annual report on progress towards the objectives of the 8th Environment Action Programme (EAP). The report provides a comprehensive overview of how well the EU is doing. (viac…)

The EU executive has presented a new vision for Europe's agri-food system by 2040, scaling back its previous, more environmentally ambitious policy in response to growing protests from farmers. The new approach to agri-food policy, presented by the European Commission on Wednesday, focuses more on simplifying regulations and making farming an attractive profession than on raising environmental standards.

With this move, the Commission is moving away from its controversial farm-to-fork strategy, which was the agri-food component of the previous mandate's flagship policy, the European Green Deal. (Gerardo Fortuna, more at euronews.com)

EU Climate Action Academy, Launched in September 2024, the Academy is the EU's digital knowledge hub on climate change and how to act, brought to you by the European Climate Change Pact. The Academy is designed to build knowledge and awareness about climate change and the steps we can all take to help fight it. The free platform offers informative courses and resources, interactive events and practical tools for taking action.

This toolkit provides you with materials to spread the word about the EU Climate Action Academy and enable your friends, family and colleagues to get involved in the fight against climate change. (More on climate-pact.europa.eu)

Net-zero energy homes use natural energy sources and are designed to consume less energy and as such are considered important in the fight against climate change. To be considered a passive house, a building must meet the following criteria:

1. Energy consumption for space heating must not exceed 15 kWh per square meter of net living area (treated floor area) per year or 10 W per square meter of peak consumption.

In climates where active cooling is required, the energy consumption requirement for space cooling roughly matches the higher heating requirements, with an additional contribution for dehumidification.

2. Renewable primary energy consumption from renewable sources (PER according to the PHI method) – the total energy to be used for all domestic applications (heating, hot water and domestic electricity) must not exceed 60 kWh per square meter of treated floor area per year for a Passive House Classic.

3. Airtightness – maximum 0.6 air changes per hour at a pressure of 50 Pascals (ACH50), as verified by on-site pressure testing (in both pressurized and unpressurized conditions).

4. Thermal comfort must be met for all living spaces in both winter and summer, with no more than 10 % hours in a given year being above 25 °C.

Passive House buildings are planned, optimized and verified using the Passive House Planning Package (PHPP).

All of the above criteria are achieved through intelligent design and implementation of the five passive house principles:

1. Design without thermal bridges

2. Top-notch windows

3. Ventilation with heat recovery

4. Quality insulation

5. Airtight construction

The following five basic principles apply when building passive houses:

1. Thermal insulation

All opaque building elements of the external envelope of the house must be very well insulated. For most cold and warm climates this means a heat transfer coefficient (U-value) of maximum 0.15 W/(m²K), i.e. maximum 0.15 watts are lost per degree of temperature difference and per square meter of external surface.

2. Windows for passive houses

Window frames must be well insulated and fitted with low-energy glass filled with argon or krypton to prevent heat transfer. For most cold and warm climates this means a U-value of 0.80 W/(m²K) or less, with g-values around 50 % (g-value = total solar transmittance, the proportion of solar energy available to the room).

3. Heat recovery from ventilation

The key is effective ventilation with heat recovery, which enables good indoor air quality and saves energy. In a passive house, at least 75 % of heat from the exhaust air is transferred back to the fresh air using a heat exchanger.

4. Airtightness of the building

Uncontrolled air leakage through gaps must be less than 0.6 air changes per hour during a pressure test at 50 Pascal (in both pressurized and unpressurized conditions).

5. Absence of thermal bridges

All edges, corners, connections and transitions must be planned and implemented with great care to avoid thermal bridges. Thermal bridges that cannot be avoided must be minimized as much as possible.

Spring

which poses a threat to rising sea levels and water shortages. New study published in the journal Nature reveals that global glaciers lost an average of 273 ± 16 gigatons per year from 2000 to 2023. This melting contributes to the increase (viac…)

SUPER-i project, funded by Horizon 2020, has developed a comprehensive tool to combat energy poverty in Europe. The tool integrates technical analyses, environmental impact assessments and innovative financial mechanisms. It offers concrete recommendations and solutions for increasing energy efficiency in Denmark, Italy and Slovenia through the SUPER-i portal. It focuses on building retrofits, renewable energy sources and greenhouse gas emission reduction. The aim is to provide stakeholders with the knowledge and tools needed to improve energy access and sustainable development. Spring

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Glossary of key terms 

• Energy poverty: A situation where households do not have sufficient access to reliable, affordable and modern energy services to meet their basic needs.
• Holistic approach: A comprehensive approach that takes into account the interconnected aspects of a problem and combines different strategies to solve it. In the case of SUPER-i, technical, environmental and financial aspects.
• Sustainability: The ability to meet the needs of the present without compromising the ability of future generations to meet their own needs. In the context of energy, it refers to the use of resources and technologies that minimize environmental impact.
• Retrofitting: Modernization of existing buildings or systems to improve their energy efficiency.
• Greenhouse gas emissions: Gases released into the atmosphere that contribute to global warming and climate change.
• Microfinance: Providing small loans or financial services to individuals or groups who do not have access to traditional banking services.
• Public-Private Partnership (PPP): A form of cooperation between the public and private sectors to finance, build, and operate infrastructure projects or public services.
• Scalability: The ability of a solution or system to be implemented on a larger scale or in other contexts.
• Stakeholder: A person, group, or organization that has an interest in or is affected by a project or activity.

This document, “A Water Resilience Strategy”, is a position paper by Water Europe (WE) aimed at supporting innovation, research and development of water technologies in Europe. The document highlights the need (viac…)

Clean Industrial Deal is a roadmap for the EU's competitiveness and decarbonisation. The aim is to transform European industry with the aim of achieving a sustainable and resilient economy by 2030. (viac…)