The heat is on: Amazon tree loss could bring 1.45 degree C local rise

The heat is on: Amazon tree loss could bring 1.45 degree C local rise

SOURCE: MongaBay DATE: May 14, 2019 SNIP: It is well known that the burning of fossil fuels and deforestation both lead to the emission of carbon dioxide, raising temperatures worldwide. Less well understood is how removing tree cover is contributing to increased temperatures at a local level – until now. In a new study published in the open-access journal PLOS ONE, scientists from Brazil’s Rio de Janeiro State University and the University of California, Santa Cruz (UCSC), have found that the temperature increase in the immediate vicinity of a deforested area could be as much as 1.45 degrees Celsius (2.6 degrees Fahrenheit) by 2050 in tropical areas such as Brazil’s Amazon basin or in the Cerrado, the nation’s savanna biome. “Everyone is familiar with how hot it is in cities compared to a forest environment, and this is because the energy is absorbed and then generates infrared radiation that heats up the environment. The same happens if you deforest,” explained study co-author Barry Sinervo of the UCSC Department of Ecology and Evolutionary Biology in a Mongabay interview. The paper explores how the albedo effect (whereby lighter-colored surfaces reflect heat, while darker ones absorb it), and the loss of evapotranspiration (whereby water goes back into the atmosphere from land, trees and plants) can both lead to warming on a local scale within deforested tropical areas. By contrast, loss of vegetative cover in sub-Arctic boreal forests has little impact on local temperatures. “We show that the heating in those [tropical] deforested habitats can have an effect at a very local scale,” Sinervo said. “And that means, even if you have an...
‘Death by a thousand cuts’: vast expanse of rainforest lost in 2018

‘Death by a thousand cuts’: vast expanse of rainforest lost in 2018

SOURCE: The Guardian DATE: April 25, 2019 SNIP: Millions of hectares of pristine tropical rainforest were destroyed in 2018, according to satellite analysis, with beef, chocolate and palm oil among the main causes. The forests store huge amounts of carbon and are teeming with wildlife, making their protection critical to stopping runaway climate change and halting a sixth mass extinction. But deforestation is still on an upward trend, the researchers said. Although 2018 losses were lower than in 2016 and 2017, when dry conditions led to large fires, last year was the next worst since 2002, when such records began. Clearcutting of primary forest by loggers and cattle ranchers in Brazil dominated the destruction, including invasions into indigenous lands where uncontacted tribes live. Losses were also high in the Democratic Republic of the Congo (DRC) and Indonesia. “We are nowhere near winning this battle,” said Frances Seymour from the World Resources Institute, part of the Global Forest Watch (GFW) network, which produced the analysis. “The world’s forests are now in the emergency room – it is death by a thousand cuts,” she said. “Band-Aid responses are not enough. For every hectare lost, we are one step closer to the scary scenario of runaway climate change.” There are many government and corporate efforts to combat deforestation, but they are not proving to be enough, Seymour said. Seymour also highlighted the direct human tragedies. “Behind the bars on these charts are heartbreaking losses in real places,” she said. “All too often the loss of an area of forest is also associated with a funeral, because every year hundreds of people are...
How vanishing lizards in Madagascar led to a troubling discovery about deforestation and climate change

How vanishing lizards in Madagascar led to a troubling discovery about deforestation and climate change

SOURCE: Yale Climate Connections DATE: April 4, 2019 SNIP: What happens within and immediately around a deforested area is obvious to anyone who has ever stumbled across a clearing in the woods. One new study shows that globally, forest cover makes land on average of 4°C (7.2°F) cooler. The effect is even stronger in dense tropical forests. Two physical phenomena explain this beneficial effect of a forest. First, bare or sparsely-vegetated land is usually darker than leafy canopy. So a clearing generally absorbs more of the Sun’s energy than a forest and reflects less sunlight back into the sky. Second, deforestation denies a plot of land the natural cooling mechanism driven by fluids circulating between trees’ roots and crowns. Trees sweat – or transpire – water vapor from the tiny pores in their leaves. The released moisture cools the space around them by the same process that chills an air conditioner unit’s air. Multiplied by the thousands of leaves that adorn typical trees, transpiration substantially lowers a forest’s temperature. [The researchers] found that clearing 50 percent of a block of tropical forest raises temperature of nearby intact jungle by 1°C (1.8°F). [Barry] Sinervo says he was “blown away” by the degree of deforestation-induced warming, especially in tropical forests, such as the Amazon. Climate change alone threatens the viability of these bastions of biodiversity. He says that for the past several decades, the effect of deforestation has been as great as that of climate change’s unflagging march, doubling the rising stress on tropical wildlife. Eduardo Maedo, a research scientist at the University of Helsinki, says that the PLOS One paper...
Logging Is the Lead Driver of Carbon Emissions from US Forests

Logging Is the Lead Driver of Carbon Emissions from US Forests

SOURCE: Earth Island Journal and Open Access Research DATE: April 4, 2019 SNIP: Protecting forest ecosystems is critical in the fight to limit global warming — when forests are disturbed they release carbon, but when left to grow they actively pull carbon out of the air and store it. When left standing, forests also provide optimal natural protection against extreme weather events, like flooding and droughts. Many people are aware of the importance of protecting rainforests in Brazil to help mitigate climate change, but few realize that more logging occurs in the US, and more wood is consumed here, than in any other nation globally. The rate and scale of logging in the Southeastern US alone is four times that in South American rainforests. The Trump Administration and industry have been aggressively promoting misinformation about forests and wildland fires, while advocating for large increases in logging under the guises of “forest health,” “fuel reduction,” “renewable energy,” and reducing carbon emissions. But the promotion of logging to supposedly curb carbon emissions is just part of the Administration’s ongoing alignment with industry and troubling pattern of climate science denial. Carbon emissions from logging in the US are ten times higher than the combined emissions from wildland fire and tree mortality from native bark beetles. Fire only consumes a minor percentage of forest carbon, while improving availability of key nutrients and stimulating rapid forest regeneration. Within a decade after fire, more carbon has been pulled out of the atmosphere than was emitted. When trees die from drought and native bark beetles, no carbon is consumed or emitted initially, and carbon emissions from...
Achievement of Paris climate goals unlikely due to time lags in the land system

Achievement of Paris climate goals unlikely due to time lags in the land system

SOURCE: Nature Climate Change DATE: February 18, 2019 SNIP: Achieving the Paris Agreement’s aim of limiting average global temperature increases to 1.5 °C requires substantial changes in the land system. However, individual countries’ plans to accomplish these changes remain vague, almost certainly insufficient and unlikely to be implemented in full. These shortcomings are partially the result of avoidable ‘blind spots’ relating to time lags inherent in the implementation of land-based mitigation strategies. [P]roper assessment of mitigation options and NDCs requires factoring in the speed with which ambition and policy translate into beneficial on-the-ground activity. Without this, unrealistic expectations about the rate and extent of mitigation will delay and eventually preclude the adoption of appropriate targets. This effect is already clear in land-based mitigation policies, which are affected by a number of time lags that are rarely anticipated in the design of mitigation policies. Partly as a result, of the 197 countries that have produced NDCs so far (representing 96.4% of global GHG emissions), no major industrialized country has yet matched its own ambitions for emissions reductions. Of 32 countries (representing 80% of anthropogenic emissions) considered by the independent scientific organization Climate Action Tracker, only two (Morocco and the Gambia) are rated as achieving ‘Paris Agreement-compatible’ implementation of their NDCs. Global CO2 emissions appear to have risen in both 2017 and 2018 after previously levelling off. We argue that such setbacks can, and must, be avoided by improved assessment and recognition of the time lags inherent in land-system policy-making, management change and feedback...