24 July 2017, Climate Central, A Nebraska-Sized Area of Forest Disappeared in 2015. A Nebraska-sized chunk of the world’s forests was decimated in 2015 because of wildfire, logging and expanding palm oil plantations, according to a new study. The loss is part of a continuing trend of deforestation that could have devastating implications for the climate. About 49 million acres of forest disappeared worldwide in 2015, mainly in North America and the tropics, putting the year’s global deforestation level at its second-highest point since data gathering began in 2001. In all, the globe lost 47 percent more forested land in 2015 than it did 16 years ago, according to the study by Global Forest Watch. Deforestation accounts for more than 10 percent of the global carbon dioxide emissions driving climate change. Dense tropical forests are also critical to keeping the climate stable because they suck up large amounts of human carbon pollution from the atmosphere, storing it in tree trunks, leaves, roots and soil. Using satellite data provided by Google and the University of Maryland, Global Forest Watch researchers measured the death or removal of trees at least 16 feet tall. 2014 was a record-breaking year for tree-cover loss when nearly 60 million acres of forests disappeared. 2015 saw less, but it’s too soon to say whether deforestation is truly on a downward swing because of uncertainty in some of the data, study co-author Mikaela Weisse, a research analyst for Global Forest Watch at the World Resources Institute, said. Read More here
Tag Archives: forest response
17 May 2017, Nature, Trees in eastern US head west as climate changes. Breaking from the general poleward movement of many species, flowering trees take an unexpected turn. Ecologists have long predicted that climate change will send plants and animals uphill and towards the poles in search of familiar temperatures. Such movements have increasingly been documented around the world. But a study now shows that changing rainfall patterns may be driving some tree species in the eastern United States west, not north. Songlin Fei, a forest ecologist at Purdue University in West Lafayette, Indiana, and his colleagues tracked the shifting distributions of 86 types of trees using data collected by the US Forest Service’s Forest Inventory and Analysis Program during two periods: from 1980 to 1995 and between 2013 and 2015 for all states. They found more species heading west than north, probably partly because of changing precipitation patterns, the team reported on 17 May in Science Advances1. “That was a huge surprise for us,” says Fei. This study suggests that, in the near-term, trees are responding to changes in water availability more than to temperature changes, he says. The team measured shifts in the centres of abundance for the 86 types of tree and found that over the past 30 years or so, 34% showed statistically significant poleward shifts at an average rate of 11 kilometres per decade. Forty-seven per cent made statistically significant westward shifts at an even faster rate — 15.4 kilometres per decade. Hardly any types of tree moved south or east. A new direction Most of the trees that shifted west were angiosperms, or flowering trees. Northbound trees were usually gymnosperms, which are mostly conifers in North America. Increased precipitation in the central United States could be one explanation for the angiosperms’ westward movement, says Fei. The increase in moisture is still subtle enough that only the more drought-tolerant and faster-growing flowering trees, which have more-efficient and robust vascular systems, can take advantage for now. Read More here
1 March 2017, Climate News Network, Spring moving forward at record rate. Spring is arriving ever earlier in the northern hemisphere. One sedge species in Greenland is now springing to growth 26 days earlier than it did a decade ago. And in the wintry United States, spring arrived 22 days early this year in Washington DC, the national capital.The evidence comes from those silent witnesses, the natural things that respond to climate signals. The relatively new science of phenology – the calendar record of first bud, first flower, first nesting behaviour and first migrant arrivals – has over the last three decades repeatedly confirmed meteorological fears of global warming as a consequence of the combustion of fossil fuels. Researchers say the evidence from the plant world is consistent with the instrumental record: 2016 was the hottest year ever recorded, and it was the third record-breaking year in succession. Sixteen of the hottest years ever recorded have happened in the 21st century. Arctic spring And the most dramatic changes are observed in the high Arctic, the fastest-warming place on the planet, according to a study in Biology Letters. As the polar sea ice retreats, the growing season gets ever longer – and arrives earlier. The pattern is not consistent: grey willow sticks to its original timetable, and dwarf birch growth has advanced about five days earlier for each decade. But the sedge, almost four weeks ahead of its timetable in a decade, holds the record, according to a study that observed one plot at a field site in West Greenland, 150 miles inland, for 12 years. Read More here
29 September 2016, The Conversation, Putting carbon back in the land is just a smokescreen for real climate action: Climate Council report. Just as people pump greenhouse gases into the atmosphere by burning fossil fuels, the land also absorbs some of those emissions. Plants, as they grow, use carbon dioxide and store it within their bodies. However, as the Climate Council’s latest report shows, Australia’s fossil fuels (including those burned overseas) are pumping 6.5 times as much carbon into the atmosphere as the land can absorb. This means that, while storing carbon on land is useful for combating climate change, it is no replacement for reducing fossil fuel emissions. Land carbon is the biggest source of emission reductions in Australia’s climate policy centrepiece – the Emissions Reduction Fund. This is smoke and mirrors: a distraction from the real challenge of cutting fossil fuel emissions.Land carbon Land carbon is part of the active carbon cycle at the Earth’s surface. Carbon is continually exchanging between the land, ocean and atmosphere, primarily as carbon dioxide. In contrast, carbon in fossil fuels has been locked away from the active carbon cycle for millions of years. Carbon stored on land is vulnerable to being returned to the atmosphere. Natural disturbances such as bushfires, droughts, insect attacks and heatwaves, many of which are being made worse by climate change, can trigger the release of significant amounts of land carbon back to the atmosphere. Changes in land management, as we’ve seen in Queensland, for example, with the relaxation of land-clearing laws by the previous state government, can also affect the capability of land systems to store carbon. Burning fossil fuels and releasing CO₂ to the atmosphere thus introduces new and additional carbon into the land-atmosphere-ocean cycle. It does not simply redistribute existing carbon in the cycle. Read More here