A longer Autumn, A Shorter Spring And A Sourer Pacific: News From The Climate Crisis “Front”
By Countercurrents
29 March, 2014
Countercurrents.org
This year, Autumn is getting longer, but Spring will be shorter. It's not the only alarming news from the climate crisis “front”.
The amount of methane entering the atmosphere will increase several times.
Invasive species in waterways are on rise due to climate crisis, and this is one of the most serious threats to global biodiversity and the leisure and tourism industries. The industry is billions of dollar worth.
And, the Pacific Ocean is turning sour much faster than expected. The cause, again, is the climate crisis created by capital with its ever increasing hunger.
A study by the University of Southampton suggests that on average the end of Autumn is taking place later in the year and Spring is starting slightly earlier. A paper with the study findings is published in the journal Remote Sensing of the Environment. [1]
The study was led by University of Southampton Professor of Geography Peter Atkinson, who worked with his colleague Dr Jadunandan Dash and in collaboration with Professor Jeganathan Chockalingam from the Department of Remote Sensing at the Birla Institute of Technology in India .
The scientists examined satellite imagery covering the northern hemisphere over a 25 year period (1982 -- 2006), and looked for any seasonal changes in vegetation by making a measure of its 'greenness'. They examined in detail, at daily intervals, the growth cycle of the vegetation -- identifying physical changes such as leaf cover, color and growth.
The study used the Global Inventory Modelling and Mapping Studies (GIMMS) dataset and combined satellite imagery with an innovative data processing method to study vegetation cycles.
Professor Atkinson says: "There is much speculation about whether our seasons are changing and if so, whether this is linked to climate change. Our study is another significant piece in the puzzle, which may ultimately answer this question."
The scientists examined the data for specific vegetation types: 'mosaic' vegetation (grassland, shrubland, forest and cropland); broad-leaved deciduous forest; needle-leaved evergreen forest; needle-leaved deciduous and evergreen forest; mixed broad-leaved and needle-leaved forest; and mixed-forest, shrubland and grassland.
They analyzed data across all the groups, recognizing that forests which have not changed size due to human intervention, for example through forestry or farming, provide the most reliable information on vegetation response to changes in our climate.
The most pronounced change found by the researchers was in the broad-leaved deciduous and needleleaved deciduous forest groups, showing that Autumn is becoming significantly later. This delay in the signs of Autumn was generally more pronounced than any evidence for an earlier onset of Spring, although there is evidence across the groups that Spring is arriving slightly earlier.
Professor Atkinson comments: "Previous studies have reported trends in the start of Spring and end of Autumn, but we have studied a longer time period and controlled for forest loss and vegetation type, making our study more rigorous and with a greater degree of accuracy.
"Our research shows that even when we control for land cover changes across the globe a changing climate is significantly altering the vegetation growth cycles for certain types of vegetation. Such changes may have consequences for the sustainability of the plants themselves, as well as species which depend on them, and ultimately the climate through changes to the carbon cycle."
Increased methane emissions
Although carbon dioxide is typically painted as the bad boy of greenhouse gases, methane is roughly 30 times more potent as a heat-trapping gas. [2]
A research finding in the journal Nature indicates that for each degree that Earth's temperature rises, the amount of methane entering the atmosphere from microorganisms dwelling in lake sediment and freshwater wetlands -- the primary sources of the gas -- will increase several times. As temperatures rise, the relative increase of methane emissions will outpace that of carbon dioxide from these sources, the researchers report.
The findings condense the complex and varied process by which methane -- currently the third most prevalent greenhouse gas after carbon dioxide and water vapor -- enters the atmosphere into a measurement scientists can use, explained co-author Cristian Gudasz, a visiting postdoctoral research associate in Princeton 's Department of Ecology and Evolutionary Biology. In freshwater systems, methane is produced as microorganisms digest organic matter, a process known as "methanogenesis."
This process hinges on a slew of temperature, chemical, physical and ecological factors that can bedevil scientists working to model how Earth's systems will contribute, and respond, to a hotter future.
The findings suggest that methane emissions from freshwater systems will likely rise with the global temperature, Gudasz said. But to not know the extent of methane contribution from such a widely dispersed ecosystem that includes lakes, swamps, marshes and rice paddies leaves a glaring hole in climate projections.
"The freshwater systems we talk about in our paper are an important component to the climate system," Gudasz said. "There is more and more evidence that they have a contribution to the methane emissions. Methane produced from natural or human made freshwater systems will increase with temperature."
To provide a simple and accurate way for climate modelers to account for methanogenesis, the scientists analyzed nearly 1,600 measurements of temperature and methane emissions from 127 freshwater ecosystems across the globe.
They found that a common effect emerged from these studies: freshwater methane generation very much thrives on high temperatures. Methane emissions at 0 degrees Celsius would rise 57 times higher when the temperature reached 30 degrees Celsius, the researchers report. For those inclined to model it, the researchers' results translated to a temperature dependence of 0.96 electron volts (eV), an indication of the temperature-sensitivity of the methane-emitting ecosystems.
"We all want to make predictions about greenhouse gas emissions and their impact on global warming," Gudasz said. "Looking across these scales and constraining them as we have in this paper will allow us to make better predictions."
Increased invasive species
One of the most serious threats to global biodiversity and the leisure and tourism industries is set to increase with climate change according to a research by Queen's University Belfast. [3]
Scientists at Queen's have found that certain invasive weeds, which have previously been killed off by low winter temperatures, are set to thrive as global temperatures increase.
The scientists based at Quercus , Northern Ireland 's Centre for Biodiversity and Conservation Science Research predicts that invasive waterweeds will become more widespread over the next 70 years.
The scientists say that additional management and legislation will be required if we are to stop the spread of these pest species.
Four species in particular could establish in areas on average 38 per cent larger than previously thought due to projected climatic warming. The water fern, parrot's feather, leafy elodea and the water primrose, are already highly problematic throughout warmer parts of Europe . Invasive species are considered to be one of the most serious threats to global biodiversity, along with climate change, habitat loss and nutrient addition.
The estimated annual cost of invasive species (plants and animals) to the UK economy is £1.8 billion, with £57 million of impact on waterways including boating, angling and waterway management.
The research findings have been published in the journal Diversity and Distributions. It looked at the global distributions of 15 invasive plant species over a 69 year period.
Dr Ruth Kelly, from the School of Biological Sciences at Queen's, who led the study, said: "Traditionally upland areas have been protected by low winter temperatures which kill off these invading weeds. Now these are likely to become increasingly vulnerable to colonization.
"On the island of Ireland currently about six per cent of the island is unsuitable for these invasive species but we think this will drop to less than one per cent by 2080. This type of research from Queen's is an example of how we are creating a more sustainable future and shows how monitoring the impact climate change is having is important for many reasons. This project will allow the NIEA and other agencies to begin their planning on how to address future issues and ensure our waterways remain a valuable economic and recreational resource."
Dr Kelly added: "It's not all bad news, however, as our most common invasive waterweed, the Canadian pondweed, is likely to become less vigorous perhaps allowing space for restoration of waterways and native plant communities."
Dr Michael Meharg, from the NIEA, said: "Invasive waterweeds can be a major problem in lakes and rivers throughout Britain and Ireland . Such plants are fast growing and often form dense mats of vegetation which may block waterways and cause problems for boating and fishing, and, therefore, to the leisure and tourism industries. Dr Kelly's research is crucial in planning for the future as we know invasive waterweeds will also out-compete native aquatic plants species and alter habitats for insects and fish."
A Sourer Pacific
Citing a study released by the US National Oceanic and Atmospheric Administration (NOAA) and University of Washington scientists Emily Atkin reports [4]:
“It's common knowledge among the scientific community that climate change will eventually acidify the oceans and turn them sour. What's less common knowledge is when exactly it will happen.
“In the tropical Pacific Ocean , however, the answers are getting a little clearer — and they're not pretty.”
Quoting the study findings Emily's report said:
“[T]he amount of carbon dioxide in the tropical Pacific has increased much faster than expected over the past 14 years, making that part of the ocean much more acidic than previously believed.
“‘We assume that most of the carbon dioxide increase [in the tropical Pacific] is due to anthropogenic CO2,' Adrienne Sutton, a research scientist with NOAA's Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington, told E&E News.
“In other words, scientists say their results show that much of the increase in carbon dioxide concentrations can be attributed to human-caused climate change. This is because, while the amount of CO2 in the atmosphere increases at a rate of about 2 parts per million (ppm) per year, parts of the tropical Pacific saw an increase in CO2 concentrations of up to 3.3 ppm per year. NOAA's study monitored CO2 levels at seven buoys in the tropical Pacific, starting in 1998.
‘It was a big surprise. We were not expecting to see rates that strong,' Sutton told E&E.”
The report said:
“Though the phrase ‘global warming' generally evokes images of a warmer atmosphere, the phenomenon arguably has an equally large impact on our oceans. When large concentrations of CO2 are released into the atmosphere, the ocean winds up absorbing about a quarter of it, according to NOAA. The CO2, in turn, makes the ocean more acidic.
“Some scientists argue that our emissions of CO2 change the chemistry of the ocean faster than it's changed for millions of years. This, according to a Wednesday report in BBC News, promises to have a detrimental effect on coral — a vital part of the ocean ecosystem.
“‘We are very concerned because the baby corals find it very hard to survive in high CO2 so reefs won't be able to repair themselves,' Katharina Fabricius from the Australian Institute of Marine Science told the BBC. ‘It's very, very serious.'
“Acidification also harms fish, making some lose their sense of smell and ‘behave recklessly in the presence of predators,' the BBC reported.
“The most recent report from the U.N.'s Intergovernmental Panel On Climate Change (IPCC) said there was high confidence that climate change will exacerbate the increase of CO2 in the atmosphere, thereby causing the oceans to absorb more and become acidic.
There is also emerging evidence that the process of ocean acidification may be coming full circle, actually contributing to climate change in itself.”
Citing an article in the journal Nature Emily added:
“[S]eawater soaking in carbon dioxide will actually cause plankton to release some of its compounds back into atmosphere.”
Note:
[1] Story Source: The story is based on materials provided by University of Southampton .
Journal Reference:
C. Jeganathan, J. Dash, P.M. Atkinson. Remotely sensed trends in the phenology of northern high latitude terrestrial vegetation, controlling for land cover change and vegetation type. Remote Sensing of Environment, 2014; 143: 154 DOI: 10.1016/j.rse.2013.11.020
Source:
University of Southampton . "Autumn ending later in northern hemisphere, research shows." ScienceDaily. ScienceDaily, 27 March 2014 . <www.sciencedaily.com/releases/2014/03/140327140040.htm>.
[2] Story Source: The story is based on materials provided by Princeton University .
Journal Reference:
Gabriel Yvon-Durocher, Andrew P. Allen, David Bastviken, Ralf Conrad, Cristian Gudasz, Annick St-Pierre, Nguyen Thanh-Duc, Paul A. del Giorgio. Methane fluxes show consistent temperature dependence across microbial to ecosystem scales. Nature, 2014; 507 (7493): 488 DOI: 10.1038/nature13164
Source:
Princeton University . "A more potent greenhouse gas than carbon dioxide, methane emissions will leap as Earth warms." ScienceDaily. ScienceDaily, 27 March 2014 . <www.sciencedaily.com/releases/2014/03/140327111724.htm>.
[3] Story Source: The story is based on materials provided by Queen's University, Belfast .
Journal Reference:
Ruth Kelly, Katie Leach, Alison Cameron, Christine A. Maggs, Neil Reid. Combining global climate and regional landscape models to improve prediction of invasion risk. Diversity and Distributions, 2014; DOI: 10.1111/ddi.12194
Source:
Queen's University, Belfast . "Invasive species in waterways on rise due to climate change." ScienceDaily. ScienceDaily, 26 March 2014 . <www.sciencedaily.com/releases/2014/03/140326101547.htm>.
[4] ThinkProgress, ClimateProgress, March 28, 2014 , “The Pacific Ocean Is Turning Sour Much Faster Than Expected, Study Shows”, http://thinkprogress.org/climate/2014/03/28/3420290/ocean-acidifying-quickly/
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