Hannah Hoag

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  • Plants flowering later on the Tibetan Plateau

    Shorter growing season linked to warmer winters on ‘the roof of the world’.

    In many regions, climate change has advanced the timing of spring events, such as flowering or the unfolding of leaves. But the meadows and steppes of the Tibetan Plateau are bucking that trend — plants are starting to bloom later in spring, making the growing season shorter. This change could threaten the livelihood of the thousands of nomads who survive by raising cattle on the plateau.

    “I’ve worked in the Tibetan Plateau region for 25 years,” says Jianchu Xu, an ethnoecologist at the World Agroforestry Centre in Kunming, China, and a professor at the Kunming Institute of Botany of the Chinese Academy of Sciences, who led the study, published this week in theProceedings of the National Academy of Sciences. Xu says he expected that plants on the plateau would follow the same pattern of early flowering seen elsewhere. In Europe, for instance, spring flowerings in 2000 occurred about 8 days earlier than they did in 1971 on average, and autumn events, such as changes in leaf colour, about 3 days earlier.

    “But then my PhD student Haiying Yu looked at more recent data” and discovered that the opposite was the case. The finding “contradicted the linear link” that is often seen between warming temperatures and an earlier start to the growing season, Xu says.

    The group used satellite data to identify the start, end and length of the growing season for the meadow and steppe vegetation of the Tibetan Plateau between 1982 and 2006, and linked it to temperature change. During this time, the mean temperature rose about 1.4 ºC on the steppes and 1.25 ºC on the lower-lying meadows.

    The study showed an initial advance in the timing of the growing season or its ‘phenology’ for both the meadow and steppe for the first 15 years. But from 2000 until 2006 that trend was reversed. The net effect was a shortening of the growing season by about one month for steppe plants and three weeks for meadow vegetation.

    Continue reading over at Nature News.

  • Canada’s climate bill flattened

    “Spitting mad,” is how the Victoria Times Colonist described Andrew Weaver, a climate modeller at the University of Victoria in British Columbia, following the news that Canada’s climate change bill had been defeated in the Senate late on Tuesday. “Retiring with a bottle of Jack Daniel’s sounds good right now,” Weaver said.

    The Climate Change Accountability Act called for greenhouse gas emissions cuts with a short-term target of 25% below the 1990 level by 2020, and a long-term target of 80% below the 1990 level by 2050. For nearly a year and a half it had shuttled between the House of Commons and its environment committee before being passed by the House on 5 May, supported by all three of Canada’s opposition parties. It then languished in the Senate, until it was voted down 43-32 this week.

    The story continues at Nature’s blog The Great Beyond

  • Canada urged to tackle scientific misconduct

    More education, advice and transparency needed to improve integrity.

    As cases of questionable conduct among scientists stack up around the globe, a report commissioned by the Canadian government calls for a rethink of the country’s research system to boost honesty and curb misconduct.

    The recommendations, if implemented, would relax privacy laws that hamper the identification of individuals and institutions found guilty of research misconduct, and create an independent council to promote best practices and prevent research misconduct.

    The Council of Canadian Academies (CCA) — a not-for-profit corporation based in Ottawa that independently assesses science relevant to public issues — released the report1 today. “We look reasonably good compared to other countries in the world, but it is the committee’s conclusion that we have to do better,” says Paul Davenport, chairman of the panel responsible for the report and former president of the University of Western Ontario in London.

    In the current system, researchers aren’t assured of equal treatment from one university to the next when accused of misconduct, says James Turk, executive director of the Canadian Association of University Teachers in Ottawa. “It is a dog’s breakfast. It is not a suitable way to deal with such an important issue, and it doesn’t instil confidence into the public, which is vital,” he says.

    Keep reading over at Nature News.

  • Sizing up the spill

    When the government began releasing estimates of the size of BP’s Gulf of Mexico oil well leak, scientists and environmental groups questioned the figures, certain the leak was larger. New research supports that notion. According to the study, published in Science, some 4.4 million barrels of oil has escaped into the ocean. It is the first independent, peer-reviewed paper on the size of the leak. (doi: 10.1126/science.1195840)

    Timothy Crone, a marine geophysicist at Columbia University’s Lamont-Doherty Earth Observatory, in Palisades, New York arrived at the estimate using a video analysis technique originally designed to study hydrothermal vents. He had spent years developing optical techniques to measure the flow of the underwater plumes that spew buoyant, superheated mineral-rich water. “Those flows are similar to what we were seeing in the oil flow event, and people were interested in what my estimates would be. People were asking what my estimates were, and I suppose I thought it was my duty,” he says.

    The story continues at Nature’ blog The Great Beyond.

  • Taxing times for Canadian postdocs

    Trainee researchers struggle to make ends meet after the government clarifies tax rules for grants.

    Staff, student or employee? The employment status of Canadian postdoctoral researchers remains unclear — and many are struggling with the tax issues that arise from the ambiguity.

    Some of Canada’s postdocs are categorized as associates with benefits, others are fellows with no employee status and, until recently, some had a tax-exempt status on a par with students. “We fall into this no-man’s land,” says Marianne Stanford, chair of the Canadian Association of Postdoctoral Scholars (CAPS) and a postdoctoral fellow at the Ottawa Hospital Research Institute in Ontario.

    Earlier this year, the federal government put an end to the tax-free wages that some postdocs had been enjoying since 2006. “Now there’s a two-tier system in labs where some of the people earning the degrees are getting more than those who already have them,” says Stanford. The move was a blow to postdocs, some of whom were recruited with the promise of tax-free earnings, and who put up with the wages because they were tax-free — although many feel they’re underpaid relative to their level of education.

    The tax-free wage came about in 2006 when the federal government introduced tax exemption for fellowships and awards. But as the government made clear in March, the exemption was only intended to apply to students enrolled in an educational programme. In a 2009 CAPS survey of 1,200 postdocs, 23% were not paying taxes on their fellowships. Many of those were in Quebec, where the provincial government considers postdocs to be stagières, or trainees, lumping them in with students.

    → Keep on reading the story in Nature