The Cleanest Air: Understanding the Pristine Air of the Southern Ocean

April 14, 2024 / activist360

Fluffy clouds and blue sky background. Credit: Photo by Engin Akyurt on Unsplash.

New Study Unveils Link Between Cloud Type, Precipitation and Air Quality Over Southern Ocean

The atmosphere over the Southern Ocean (SO) is noted for being exceptionally clean, largely untouched by anthropogenic or terrestrial emissions. This quality makes the SO an ideal natural laboratory for studying pre-industrial climate conditions and the interactions between aerosols, clouds, and precipitation.

A recent study published in Nature delves into the intricacies of aerosol removal by precipitation. Researchers from Monash University, the Australian Research Council, and other institutions analyzed several years of observational data from the Kennaook/Cape Grim Observatory in Tasmania. They focused on two distinct cloud patterns: open puffy mesoscale cellular convection (MCC) and closed flat MCC. Here are the key takeaways from the study:

Key Findings

Cloud Type and Rainfall: The study found that open, puffy clouds produced heavier and more frequent rainfall (1.72 mm per day, occurring around 17% of the time) compared to closed, flat clouds (0.29 mm per day, occurring only 4.5% of the time).
Connection to Air Quality: Surprisingly, the researchers observed lower levels of tiny particles (called cloud condensation nuclei or CCN) in the air during periods when open, puffy clouds dominated (69 particles per cubic centimeter) compared to when closed, flat clouds dominated (89 particles per cubic centimeter). This suggests that the heavier rainfall from open clouds may be “cleaning out” the atmosphere through a process called wet deposition.
Seasonal Variations: The inverse relationship between rainfall and CCN levels held true across different seasons, with the most pristine air observed during the winter months when open clouds dominated. The study also noted that open clouds were most frequent during the winter. These cycles suggest a robust interplay between the oceanic emissions and the atmospheric conditions over the year.
Weather Influences: The study highlighted the crucial role played by weather factors, such as atmospheric stability and surface air pressure patterns, in influencing the cloud shape, rainfall rates, and ultimately, the observed CCN levels.
Daily Cycle: Interestingly, while rainfall peaked in the early morning hours, the CCN cycle was out of phase, suggesting that weather factors, rather than CCN levels, were the primary drivers of the daily rainfall cycle.

These findings underscore the complex interplay between clouds, precipitation, and aerosols in the remote Southern Ocean region. The study suggests that the heavier precipitation from open cellular cloud patterns may be removing or washing out more particles from the atmosphere.

Implications for Climate Models

The detailed observation of wet deposition mechanisms and their interaction with CCN offers valuable insights into cloud formation and precipitation processes. These insights help refine climate models, particularly in predicting the radiative balance and hydrological responses of the earth’s system under varying climatic conditions.

Final Thoughts

Understanding how aerosols, clouds, and precipitation interact over the Southern Ocean is important because it helps improve climate models, making them better at predicting weather and climate changes. This is important for humanity to enhance our ability to prepare for and adapt to future environmental changes and extreme weather events, which can have significant impacts on agriculture, water resources, and overall human well-being.

Source: Alinejadtabrizi, T., Lang, F., Huang, Y., Ackermann, L., Keywood, M., Ayers, G., Krummel, P., Humphries, R., Williams, A. G., Siems, S. T., & Manton, M. (2024). Wet deposition in shallow convection over the Southern Ocean. npj Climate and Atmospheric Science.

How Reforestation in the Eastern United States Combats Climate Change: A Century’s Insight

February 18, 2024 / activist360

Borley wood – restoration This view shows a area from which planted exotic conifer species have just been removed to allow site native species to re-assert themselves (NVC W8 ash/maple woodland type), October 17, 2006.

A recent study “A Century of Reforestation Reduced Anthropogenic Warming in the Eastern United States” unveils a silver lining through the lens of historical reforestation efforts in the Eastern United States. Spanning over a century, these endeavors have contributed to the greening of landscapes and played a pivotal role in reducing anthropogenic warming across the region. This study revealed the significant impact of reforestation on local climate mitigation and underscores the potential of nature-based solutions in our fight against global warming.

The Cooling Effect of Reforestation

The research, conducted by a team of environmental scientists, reveals that reforestation in the Eastern U.S. has led to a noticeable cooling of both land surface and near-surface air temperatures. By analyzing ground and satellite-based observations, the study highlights a significant reduction in temperatures, with forests cooling the land surface by 1–2°C annually compared to adjacent grasslands and croplands. This cooling effect is most pronounced during the growing season’s midday, offering a natural buffer against the rising temperatures associated with climate change.

A Shift in Climate Trends

Interestingly, the study correlates the extensive reforestation efforts with the anomalous lack of warming in the Eastern U.S. throughout the 20th century. Unlike other North American regions that experienced substantial warming, the Eastern U.S. showed minor cooling trends, attributed to the biophysical impacts of reforestation. This phenomenon, often referred to as the “warming hole,” underscores the potential of strategic reforestation efforts in tempering regional climate trends.

Implications for Climate Adaptation

The findings of this study underscore reforestation’s dual benefits: sequestering carbon dioxide from the atmosphere and directly cooling the Earth’s surface. In the face of escalating climate change, reforestation emerges as a vital nature-based solution, offering a sustainable pathway for climate adaptation and mitigation. The study’s insights highlight the importance of preserving and expanding forested areas as a proactive measure against global warming.

Renewed Focus on Reforestation & Conservation

As we move forward, the study calls for a renewed focus on reforestation and forest conservation as key strategies in the global climate action agenda. By learning from the century-long reforestation efforts in the Eastern U.S., we can harness the power of nature to forge a cooler, more sustainable future for our planet.

The study provides compelling evidence of reforestation’s positive impact on climate. It serves as a call to action for policymakers, environmentalists, and communities worldwide to invest in reforestation as a practical and impactful climate solution.

Harmony with Nature: A Core Principle in Major Religions

December 10, 2023 / activist360

*Yosemite Valley, among the trees, in June 2023.*

In a world increasingly focused on environmental conservation, it’s enlightening to explore how major religions respect and honor nature. These ancient faiths provide a rich tapestry of beliefs and practices that highlight the sacred bond between humans and the natural world.

Let’s take a look at how major religions prize harmony with nature:

Buddhism: Mindful Stewardship of Nature

Buddhism teaches the interconnectedness of all living things, promoting a deep respect for nature. The concept of ‘Ahimsa,’ or non-violence, extends to all living beings, fostering a mindful approach to environmental stewardship. The ancient Hindu texts discourage wanton destruction of nature including of wild and cultivated plants.

The forest is a peculiar organism of unlimited kindness and benevolence that makes no demands for its sustenance and extends generously the products of its life activity; it affords protection to all beings, offering shade even to the axe-man who destroys it.
―Gautama Buddha

Hinduism: Divine in Nature

Hinduism views nature as a manifestation of the divine. The reverence for rivers, mountains, flora, and fauna in Hindu texts underscores the faith’s ecological ethos. The Earth is often personified as the goddess ‘Bhumi,‘ reinforcing the sanctity of the natural world.

Mother Earth, may whatever I dig from you grow back again quickly, and may we not injure you by our labour.
—Atharva Veda

Christianity: Stewardship of God’s Creation

Christianity advocates for stewardship of the Earth, viewed as God’s creation. Biblical scriptures, such as Genesis, emphasize humanity’s role in caring for and preserving the environment. In Genesis, God instructs humanity to manage the creation in particular ways.

And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.
—Genesis 1:26–28

Islam: Nature as a Sign of God

In Islam, nature is seen as a tapestry of signs pointing to the divine. The Quran frequently references the environment, urging believers to protect and respect it as a gift from Allah.

“And Allah has sent down rain from the sky and given life thereby to the earth after its lifelessness. Indeed in that is a sign for a people who listen.”
—Quran, 16:65

Judaism: Balancing Use and Preservation

Judaism teaches a balance between utilizing and preserving nature. The concept of ‘Bal Tashchit‘—do not destroy—highlights a commitment to avoiding wastefulness and promoting sustainability.

If not for the trees, human life could not exist.
—BT Taanit 23a

Each of these faiths brings a unique perspective to environmental ethics, yet they all share a profound respect for the natural world. This universal reverence underscores the importance of collaboration across religious lines for the conservation and protection of our planet.