Birds in larger mature forest areas, on the other hand, were better able to withstand the dry conditions since these areas offer more shade and resources. Forest cover helps maintain climatic conditions, including moist soil, which is an important factor for wood thrush food availability
According to a new study by biologists at Virginia Tech and the Smithsonian Migratory Bird Center, the offspring of a certain songbird, the wood thrush, are more likely to survive drought in larger forest plots that offer plenty of shade and resources…
Wood thrush are common to the United States, but populations have declined by more than 60 percent since the 1960s. In addition, many species of songbirds, such as blue jays, robins, and cardinals, as well as wood thrush, face the highest risk of dying within the first five days of leaving their nests.
…Birds in larger mature forest areas, on the other hand, were better able to withstand the dry conditions since these areas offer more shade and resources. Forest cover helps maintain climatic conditions, including moist soil, which is an important factor for wood thrush food availability. These conditions ultimately make areas more resilient to drought.
“The research highlights the role that forest cover can play in buffering animals from stressful environmental conditions — in this case, promoting survival of young birds during drought conditions,” said Amanda Rodewald, professor and director of conservation science at the Cornell Lab of Ornithology, who was not involved with the research. “This finding is yet another that underscores the importance of maintaining forested landscape mosaics in strategies to conserve biodiversity.”….
For ideal survival, then, Vernasco says fledglings do well with a “mosaic” of habitats made up of forests that differ in age and thus vegetation structure.
Ben J. Vernasco, T. Scott Sillett, Peter P. Marra, T. Brandt Ryder. Environmental predictors of nestling condition, postfledging movement, and postfledging survival in a migratory songbird, the Wood Thrush (Hylocichla mustelina). The Auk, 2017; 135 (1): 15 DOI: 10.1642/AUK-17-105.1
…California is facing its own threat of bigger and more destructive storms. Mounting research, much of it done in the wake of the near-record rains that pulled California out of a five-year drought this past winter, shows that seasonal soakers may not come as often as they used to, but could pack more punch when they do arrive.
Frequencies of extreme precipitation are projected to increase over Northern Hemisphere- especially Califormia- where projected warming is strongest.
California’s more nuanced hydrological future reflects a precarious balance between the expanding subtropical high from the south and the south-eastward extending Aleutian low from the north-west– bolstering more extreme precipitation events.
More drought expected over Mediterranean basin due to decreased winter precipitation.
ABSTRACT: In most Mediterranean climate (MedClim) regions around the world, global climate models (GCMs) consistently project drier futures. In California, however, projections of changes in annual precipitation are inconsistent. Analysis of daily precipitation in 30 GCMs reveals patterns in projected hydrometeorology over each of the five MedClm regions globally and helps disentangle their causes. MedClim regions, except California, are expected to dry via decreased frequency of winter precipitation. Frequencies of extreme precipitation, however, are projected to increase over the two MedClim regions of the Northern Hemisphere where projected warming is strongest. The increase in heavy and extreme precipitation is particularly robust over California, where it is only partially offset by projected decreases in low-medium intensity precipitation. Over the Mediterranean Basin, however, losses from decreasing frequency of low-medium-intensity precipitation are projected to dominate gains from intensifying projected extreme precipitation. MedClim regions are projected to become more sub-tropical, i.e. made dryer via pole-ward expanding subtropical subsidence. California’s more nuanced hydrological future reflects a precarious balance between the expanding subtropical high from the south and the south-eastward extending Aleutian low from the north-west. These dynamical mechanisms and thermodynamic moistening of the warming atmosphere result in increased horizontal water vapor transport, bolstering extreme precipitation events.
According to climate models, by the end of this century, the western United States is still projected to warm by about another 3.5 degrees Celsius,” he told me. “And when we remember that the relationship between temperature and fire is exponential … we’re really talking about a very different western United States in 50 years.
This wasn’t supposed to be a bad year for Western wildfires.Last winter, a weak La Niña bloomed across the Pacific. It sent flume after flume of rain to North America and irrigated half the continent. Water penetrated deep into the soil of Western forests, and mammoth snowdrifts stacked up across the Sierra Nevadas. California’s drought ended in the washout.
In other words, the weeks of heat that baked the West in July and August were enough to wipe away some of the fire-dampening effect of the winter storms…
…“According to climate models, by the end of this century, the western United States is still projected to warm by about another 3.5 degrees Celsius,” he told me. “And when we remember that the relationship between temperature and fire is exponential … we’re really talking about a very different western United States in 50 years.”…
Land use change and drought favor the same species and threaten the same species so we may be losing biodiversity faster than we previously thought when we were studying these separately
Key strategies include protecting areas of wetter forests that expected to stay wet in the future; targetting conservation on wet-forest species that are particularly sensitive to habitat conversion and climate change; and incentivizing landowners in wet regions to create or maintain patches of forests near or within their farms to better balance food production and biodiversity.
Climate change and habitat conversion to agriculture are working together to homogenize nature, indicates a study in the journal Global Change Biology led by the University of California, Davis.
In other words, the more things change, the more they are the same.
While the individual impacts of climate change and habitat conversion on wildlife are well-recognized, little is known about how species respond to both stressors at once.
In northwest Costa Rica, the study’s authors surveyed birds and plants at 120 sites that included rainforests, dry forests and farmland to determine how habitat conversion and climate-change-induced droughts affect tropical wildlife. They found that different bird species thrive in drier versus wetter areas of forests. In farmlands however, birds associated with dry sites were found everywhere, even in the wettest sites.
“Across Central and South America, we are seeing large areas being converted from native forest to agriculture, and droughts are becoming more frequent,” said lead author Daniel Karp, an assistant professor in the UC Davis Department of Wildlife, Fish and Conservation Biology. “Both of these global pressures are favoring the same species and threatening the same species This means we may be losing biodiversity faster than we previously thought when we were studying climate change and habitat conversion individually.”
…most vulnerable birds at the study sites were those in the wet forests, which include tropical birds like tanagers, manakins, and woodcreepers. He noted that birds in the agricultural sites — such as blackbirds, doves, and sparrows — were more similar to those found in the dry forest, where there is less of a tree canopy and more grass cover….
Daniel S. Karp, Luke O. Frishkoff, Alejandra Echeverri, Jim Zook, Pedro Juárez, Kai M. A. Chan. Agriculture erases climate-driven β-diversity in Neotropical bird communities. Global Change Biology, 2017; DOI: 10.1111/gcb.13821
‘California Climate Science and Solutions Institute’ would fund basic- and applied-research projects designed to help the state to grapple with the hard realities of global warming with revenue from the state’s cap and trade program
California has a history of going it alone to protect the environment. Now… scientists in the Golden State are sketching plans for a home-grown climate-research institute — to the tune of hundreds of millions of dollars per year.
The initiative, which is backed by California’s flagship universities, is in the early stages of development. If it succeeds, it will represent one of the largest US investments in climate research in years. The nascent ‘California Climate Science and Solutions Institute’ would fund basic- and applied-research projects designed to help the state to grapple with the hard realities of global warming.
The project could be funded by revenue from the state’s cap-and-trade programme to reduce greenhouse-gas emissions, but its political prospects are unclear. Advocates say they have received a warm reception from California Governor Jerry Brown, but a spokesperson for Brown would say only that “discussions are ongoing”. The proposal must also clear the state legislature….
But the California initiative still faces significant challenges. Severin Borenstein, an economist at the University of California, Berkeley, warns that academics will face plenty of competition for a limited pool of cap-and-trade revenue…..Nonetheless, Borenstein favours the climate initiative, because he sees global warming as an issue on which California can have a truly global impact.
“The main way California can contribute to dealing with climate change is through innovation,” he says. “We can invent and test the technologies and processes that will allow the rest of the world to reduce their greenhouse-gas emissions.”
Drier soils and reduced water flow in rural areas — but more intense rainfall that overwhelms infrastructure and causes flooding and stormwater overflow in urban centers. That’s the finding of an exhaustive study of the world’s river systems, based on data collected from more than 43,000 rainfall stations and 5,300 river monitoring sites across 160 countries…
…”The [study] relied on observed flow and rainfall data from across the world, instead of uncertain model simulations, means we are seeing a real-world effect — one that was not at all apparent before.”
“It’s a double whammy,” said Conrad Wasko, lead author of the paper and postdoctoral fellow at UNSW’s Water Research Centre. “People are increasingly migrating to cities, where flooding is getting worse. At the same time, we need adequate flows in rural areas to sustain the agriculture to supply these burgeoning urban populations.”
…[the study] found warmer temperatures lead to more intense storms, which makes sense: a warming atmosphere means warmer air, and warmer air can store more moisture…But…why is flooding not increasing at the same rate as the higher rainfall?
The answer turned out to be the other facet of rising temperatures: more evaporation from moist soils is causing them to become drier before any new rain occurs — moist soils that are needed in rural areas to sustain vegetation and livestock. Meanwhile, small catchments and urban areas, where there are limited expanses of soil to capture and retain moisture, the same intense downpours become equally intense floods, overwhelming stormwater infrastructure and disrupting life.
Global flood damage cost more than US$50 billion in 2013; this is expected to more than double in the next 20 years as extreme storms and rainfall intensify and growing numbers of people move into urban centres. Meanwhile, global population over the next 20 years is forecast to rise another 23% from today’s 7.3 billion to 9 billion — requiring added productivity and hence greater water security….
“We need to adapt to this emerging reality,” said Sharma. “We may need to do what was done to make previously uninhabitable places liveable: engineer catchments to ensure stable and controlled access to water. Places such as California, or much of the Netherlands, thrive due to extensive civil engineering. Perhaps a similar effort is needed to deal with the consequences of a changing climate as we enter an era where water availability is not as reliable as before.”…
Conrad Wasko, Ashish Sharma. Global assessment of flood and storm extremes with increased temperatures. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-08481-1
As drought and water shortages become California’s new normal, more and more of the water that washes down drains and flushes down toilets is being cleaned and recycled for outdoor irrigation. But some public officials, taking cues from countries where water scarcity is a fact of life, want to take it further and make treated wastewater available for much more — even drinking. “This is a potential new source of water for California,” said former Assemblyman Rich Gordon. “We need to find water where we can.”
….Water recycling is more the norm in countries like Singapore, Israel, Saudi Arabia and Australia, which have long had water shortages. Israel reclaims about 80 percent of its wastewater, while Singapore reclaims almost 100 percent. The reclaimed water is extensively used to irrigate agricultural lands and recharge aquifers in Israel, while most of Singapore’s water is used for industrial purposes.
….To address the public perception issue, former Assemblyman Gordon was able to pass Assembly Bill 2022 last year. It enables water agencies in the state to distribute bottles of advanced purified recycled water for educational purposes….
A new approach for identifying the impacts of climate change and extreme weather on the variability of global and regional wheat production has been proposed by researchers. The study analyzed the effect of heat and water anomalies on crop losses over a 30-year period… [the study] finds that heat stress concurrent with drought or water excess can explain about 40% of the changes in wheat yields from one year to another.
….One finding is that in contrast to the common perception, water excess affects wheat production more than drought in several countries. Excessive precipitation and greater cloud cover, especially during sensitive development stages of the crop, are major contributors to reduced yields, as they help pests and disease proliferate and make it harder for the plants to get the oxygen and light they need….
M Zampieri, A Ceglar, F Dentener, A Toreti. Wheat yield loss attributable to heat waves, drought and water excess at the global, national and subnational scales. Environmental Research Letters, 2017; 12 (6): 064008 DOI: 10.1088/1748-9326/aa723b
The expansion of grasslands isn’t solely due to drought, but more complex climate factors are at work, both for modern Africans now and ancient Africans in the Pleistocene, suggests new research….
Researchers from the University of Utah have found a better way. By analyzing isotopes of oxygen preserved in herbivore teeth and tusks, they can quantify the aridity of the region and compare it to indicators of plant type and herbivore diet. The results show that, unexpectedly, no long-term drying trend was associated with the expansion of grasses and grazing herbivores. Instead, variability in climate events, such as rainfall timing, and interactions between plants and animals may have had more influence on our ancestors’ environment. This shows that the expansion of grasslands isn’t solely due to drought, but more complex climate factors are at work, both for modern Africans now and ancient Africans in the Pleistocene.
Scott A. Blumenthal, Naomi E. Levin, Francis H. Brown, Jean-Philip Brugal, Kendra L. Chritz, John M. Harris, Glynis E. Jehle, Thure E. Cerling. Aridity and hominin environments. Proceedings of the National Academy of Sciences, 2017; 201700597 DOI: 10.1073/pnas.1700597114