Can we still stop global warming?

Wildfires burn more severely and more often, urban noise pollution is becoming a global threat to public health, and phenological mismatches – disruptions in the timing of life cycle stages in natural systems – have ecological consequences. These critical environmental issues, which require greater attention, are highlighted in the new Frontiers report released today by the United Nations Environment Program (UNEP).

This is the fourth edition of the Frontières report, which was first published in 2016 with an alert on the growing risk of zoonotic diseasesfour years before the outbreak of the Covid-19 pandemic.

“The Frontiers Report identifies and proposes solutions to three environmental problems that deserve the attention and action of governments and the general public,” said Inger Andersen, Executive Director of UNEP. “Urban noise pollution, wildfires and phenological change – the three topics of this Frontiers report – are issues that underscore the urgency of addressing the triple planetary crisis of climate change, pollution and the loss of biodiversity.”

The latest edition of the Frontières report, Noise, fires and mismatches: emerging environmental issuesis published a few days before the resumed fifth session of the United Nations Environment Assembly (UNEA):

Noise pollution in cities is a growing danger to public health

Unwanted, prolonged, high-level noise from road traffic, railways, or recreational activities harm human health and well-being. This includes chronic discomfort and sleep disorderleading to serious heart disease and metabolic disorders such as Diabeteshearing loss and poor mental health.

Noise pollution is already the cause of 12,000 premature deaths each year in the EU and affects one in five EU citizens. Acceptable noise levels are exceeded in many cities around the world, including Algiers, Bangkok, Damascus, Dhaka, Ho Chi Minh City Ibadan, Islamabad and New York.

are particularly affected the very young, the elderly and marginalized communities close heavy traffic roads, industrial areas and far from green spaces.

It is also a threat to animalsaltering the communications and behavior of various species, including birds, insectsand amphibians.

At the same time, natural sounds can provide various health benefits. Urban planners should prioritize noise reduction at source; investments in alternative mobility; and urban infrastructure that creates positive soundscapes such as tree belts, green walls, green roofs and more green spaces in cities.

Positive examples include London Ultra Low Emission Zonethat of Berlin new cycle paths on wide roadsand Egypt national noise control plan.

COVID-19 lockdowns have led to a new appreciation for green spaces and urban traffic noise reduction. Programs aimed at “building back better” represent an underutilization opportunity for policy makers, planners and communities to create additional green spaces for all.

Dangerous wildfire weather expected to worsen

Every year, between 2002 and 2016, an average of about 423 million hectares or 4.23 million square kilometers of the Earth’s land surface – an area the size of the entire European Union – burned, becoming more common in mixed forest and savannah ecosystems. An estimated 67% of the annual global area burned by all types of fires, including wildfires, was on the African continent.

Dangerous wildfire weather conditions are projected become more frequent and more intense and last longer, including in areas previously unaffected by the fires. Extremely intense wildfires can trigger thunderstorms in smoke channels that aggravate fires with erratic wind speeds and generate lightning that ignites other fires far beyond the fire front, a dangerous feedback loop.

This is due to climate change, including warmer temperatures and drier conditions with droughts. Land-use change is another risk factor, including commercial logging and deforestation for farms, pastures and urban expansion. Another cause of wildfire proliferation is aggressive natural fire suppression, which is essential in some natural systems to limit the amounts of combustible materials, and inappropriate fire management policies that exclude traditional fire management practices. and indigenous knowledge.

The long-term effects on human health go beyond those fight forest fires, evacuatedWhere suffer losses. Smoke and particulates from wildfires have significant health consequences in downwind settlements, sometimes thousands of miles from the source, with impacts often exacerbated in people with pre-existing disease, women, children, the elderly and the poor. Changes in fire regimes are also expected to cause massive loss of biodiversity, putting more than 4,400 terrestrial and freshwater species.

Wildfires generate black carbon and other pollutants that can pollute water sources, promote the melting of glaciers, cause landslides and large-scale algal blooms in the oceans, and transform the sinks of carbon such as tropical forests into carbon sources.

Report calls for more investment in wildfire risk reduction; the development of prevention and response management approaches that include vulnerable, rural, traditional and indigenous communities; and other improvements in remote sensing capabilities, such as satellites, radar, and lightning detection.

Climate change is disrupting the natural rhythms of plants and animals

Phenology is the timing of recurring life cycle stages driven by environmental forces, and how, within an ecosystem, interacting species respond to changing conditions. Plants and animals in terrestrial, aquatic and marine ecosystems use temperature, day length or rainfall as cues to know when to unfold leaves, flower, bear fruit, reproduce, nest, pollinate, migrate or transform in another way.

Phenological changes occur when species alter the timing of life cycle stages in response to changing environmental conditions altered by climate change. The problem is that interacting species in an ecosystem do not always change the timing in the same direction or at the same rate.

These phenological changes are increasingly disrupted by climate change, pushing plants and animals out of sync with their natural rhythms and leading to mismatches, such as when plants change life cycle stages faster than herbivores.

Long-distance migrants are particularly vulnerable to phenological changes. Local weather signals that normally trigger migration may no longer accurately predict conditions at their destination and at resting sites along the route.

Phenological changes in crops in response to seasonal variations will be difficult for food production in the face of climate change. Changes in the phenology of commercially important marine species and their prey have important consequences on the productivity of the stocks and the fishery.

The full effects of phenological mismatches require further research. Maintain suitable habitats and ecological connectivitystrengthen the integrity of biological diversity, coordinate international efforts along the migratory routes, supporting resilience and maintaining genetic variation within species are crucial conservation goals. Above all, limit the rate of warming by reducing CO2 emissions is essential.

Teresa H. Sadler