No Apparent Spike of Carbon dioxide Across Cretaceous-Paleogene Boundary

Global trends of pCO2 across the Cretaceous–Paleogene boundary supported by the first Southern Hemisphere stomatal proxy-based pCO2 reconstruction

Authors:

Steinthorsdottir et al

Abstract:

Reliable reconstructions of atmospheric carbon dioxide concentrations (pCO2) are required at higher resolution than currently available to help resolve the relationship between mass extinctions and changes in palaeo-pCO2 levels. Such reconstructions are needed: 1, at a high temporal resolution for constraining the pre- and post-extinction atmospheres; and 2, at a sufficient spatial resolution to constrain potential inter-hemispheric differences. Here we estimate pCO2 based on fossil Lauraceae leaf cuticle specimens derived from three localities with strata spanning the latest Cretaceous to the mid-Paleocene, including a new Cretaceous–Paleogene boundary (K–Pg) locality, in New Zealand. We use two independent methods of stomatal density-based pCO2 reconstructions; a transfer function calibrated using herbarium material and the stomatal ratio method, producing three calibration sets. Our results based on the mean values of each of the three calibration methods indicate pCO2 ranging between ca. 460 and 650 ppm during the latest Cretaceous, falling precipitously to average values between ca. 360 and 430 ppm across the K–Pg boundary, and further to ca. 305–320 ppm in the mid-Paleocene. A ‘spike’ of extremely high pCO2 at the K–Pg could not be confirmed, but our results are, nonetheless, consistent with previously published pCO2 records from the Northern Hemisphere, and show that stomatal density worldwide was responding to significant changes in pCO2 across the K–Pg.

The Strontium Cycle of the NeoProterozoic was Driven by Seemingly Unique Paleogeography

Paleogeographic forcing of the strontium isotopic cycle in the Neoproterozoic

Authors:

Goddéris et al

Abstract:

The period spanning from 825 to 540 Ma is characterized by major changes in the surficial Earth system. This extraordinary interval starts with the breakup of the Rodinia supercontinent and eruption of a series of large igneous provinces and ends with the assembly of Gondwana, giving rise to the Pan-African orogenies. This paleogeographic reorganization is accompanied by a global climatic cooling, including the paroxysmal Cryogenian “snowball” glacial events. The 87Sr/86Sr of seawater displays a major long-term rise over this interval that is punctuated by episodic, smaller declines and inflections. We use a coupled deep time climate-carbon numerical model to explore the complex role of tectonics and climate on this distinct evolution in seawater 87Sr/86Sr. We show that the modulation of the weathering of the erupted large igneous provinces by continental drift explains the changes in seawater 87Sr/86Sr from 800 to 635 Ma. The subsequent sharp rise in seawater 87Sr/86Sr from 635 to 580 Ma is the result of erosion of radiogenic crust exposed in the Pan-African orogens. Coeval evolution of atmospheric CO2 displays a decrease from about 80 times the pre-industrial level around 800 Ma to 5 times just before the beginning of the Phanerozoic.

An Isotopic Anomaly With Regards to CO2 Atmospheric Concentration for the PETM

Temperature and atmospheric CO2 concentration estimates through the PETM using triple oxygen isotope analysis of mammalian bioapatite

Authors:

Gehler et al

Abstract:

The Paleocene–Eocene Thermal Maximum (PETM) is a remarkable climatic and environmental event that occurred 56 Ma ago and has importance for understanding possible future climate change. The Paleocene–Eocene transition is marked by a rapid temperature rise contemporaneous with a large negative carbon isotope excursion (CIE). Both the temperature and the isotopic excursion are well-documented by terrestrial and marine proxies. The CIE was the result of a massive release of carbon into the atmosphere. However, the carbon source and quantities of CO2 and CH4 greenhouse gases that contributed to global warming are poorly constrained and highly debated. Here we combine an established oxygen isotope paleothermometer with a newly developed triple oxygen isotope paleo-CO2 barometer. We attempt to quantify the source of greenhouse gases released during the Paleocene–Eocene transition by analyzing bioapatite of terrestrial mammals. Our results are consistent with previous estimates of PETM temperature change and suggest that not only CO2 but also massive release of seabed methane was the driver for CIE and PETM.

Iceland has Demonstrated how to Sequester and Convert Carbon dioxide to Stone

cientists and engineers working at a major power plant in Iceland have shown for the first time that carbon dioxide emissions can be pumped into the earth and changed chemically to a solid within months--radically faster than anyone had predicted. The finding may help address a fear that so far has plagued the idea of capturing and storing CO2 underground: that emissions could seep back into the air or even explode out. A study describing the method appears this week in the leading journal Science.

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Changing atmospheric CO2 concentration was the primary driver of early Cenozoic climate

Changing atmospheric CO2 concentration was the primary driver of early Cenozoic climate

Authors:

Anagnostou et al

Abstract:

The Early Eocene Climate Optimum (EECO, which occurred about 51 to 53 million years ago)1, was the warmest interval of the past 65 million years, with mean annual surface air temperature over ten degrees Celsius warmer than during the pre-industrial period2, 3, 4. Subsequent global cooling in the middle and late Eocene epoch, especially at high latitudes, eventually led to continental ice sheet development in Antarctica in the early Oligocene epoch (about 33.6 million years ago). However, existing estimates place atmospheric carbon dioxide (CO2) levels during the Eocene at 500–3,000 parts per million5, 6, 7, and in the absence of tighter constraints carbon–climate interactions over this interval remain uncertain. Here we use recent analytical and methodological developments8, 9, 10, 11 to generate a new high-fidelity record of CO2 concentrations using the boron isotope (δ11B) composition of well preserved planktonic foraminifera from the Tanzania Drilling Project, revising previous estimates6. Although species-level uncertainties make absolute values difficult to constrain, CO2 concentrations during the EECO were around 1,400 parts per million. The relative decline in CO2 concentration through the Eocene is more robustly constrained at about fifty per cent, with a further decline into the Oligocene12. Provided the latitudinal dependency of sea surface temperature change for a given climate forcing in the Eocene was similar to that of the late Quaternary period13, this CO2 decline was sufficient to drive the well documented high- and low-latitude cooling that occurred through the Eocene14. Once the change in global temperature between the pre-industrial period and the Eocene caused by the action of all known slow feedbacks (apart from those associated with the carbon cycle) is removed2, 3, 4, both the EECO and the late Eocene exhibit an equilibrium climate sensitivity relative to the pre-industrial period of 2.1 to 4.6 degrees Celsius per CO2 doubling (66 per cent confidence), which is similar to the canonical range (1.5 to 4.5 degrees Celsius15), indicating that a large fraction of the warmth of the early Eocene greenhouse was driven by increased CO2 concentrations, and that climate sensitivity was relatively constant throughout this period.

The World is Greening due to Increased Carbon dioxide

From a quarter to half of Earth's vegetated lands has shown significant greening over the last 35 years largely due to rising levels of atmospheric carbon dioxide, according to a new study published in the journal Nature Climate Change on April 25.

An international team of 32 authors from 24 institutions in eight countries led the effort, which involved using satellite data from NASA's Moderate Resolution Imaging Spectrometer and the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer instruments to help determine the leaf area index, or amount of leaf cover, over the planet's vegetated regions. The greening represents an increase in leaves on plants and trees equivalent in area to two times the continental United States.

Green leaves use energy from sunlight through photosynthesis to chemically combine carbon dioxide drawn in from the air with water and nutrients tapped from the ground to produce sugars, which are the main source of food, fiber and fuel for life on Earth. Studies have shown that increased concentrations of carbon dioxide increase photosynthesis, spurring plant growth.

However, carbon dioxide fertilization isn't the only cause of increased plant growth--nitrogen, land cover change and climate change by way of global temperature, precipitation and sunlight changes all contribute to the greening effect. To determine the extent of carbon dioxide's contribution, researchers ran the data for carbon dioxide and each of the other variables in isolation through several computer models that mimic the plant growth observed in the satellite data.

Results showed that carbon dioxide fertilization explains 70 percent of the greening effect, said co-author Ranga Myneni, a professor in the Department of Earth and Environment at Boston University. "The second most important driver is nitrogen, at 9 percent. So we see what an outsized role CO2 plays in this process."

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Atmospheric carbon dioxide and climate change since the Late Jurassic

Atmospheric carbon dioxide and climate change since the Late Jurassic (150 Ma) derived from a global carbon cycle model

Author:

Kashiwagi et al

Abstract:

A global carbon cycle model covering the Late Jurassic Period to Recent (150–0 Ma) with subaerial metamorphism and continental and oceanic hot spot volcanism was constructed. The model's results indicate that the OAE1a and Valanginian OAE (OAE: oceanic anoxic event) in the Cretaceous Period are related to increased atmospheric CO2 level due to hot spot volcanism. Furthermore, the model results based on high-resolution geochemical records demonstrate that decreases in CO2 associated with the termination of the OAE1a, OAE2, and perhaps the Valanginian OAE are attributable to a large amount of organic carbon burial. Moreover, the model results indicate that enhanced continental weathering and carbonate precipitation contributed to the decrease in atmospheric CO2 during the OAE1a period.

A comparison of the model results with proxy estimates of atmospheric CO2 indicates that CO2 degassings from the lithosphere and mantle, including those from subaerial metamorphism, partly contributed to high levels of atmospheric CO2 in the middle Cretaceous and the Eocene, but they are not sufficiently decisive to account for the suggested CO2 levels by the proxies. Differences in estimated CO2 between the model and the proxies in the middle Cretaceous can be explained by a complex evolution of the terrestrial plants from gymnosperms to angiosperms, and/or continental weathering assisted by arbuscular mycorrhizal and ectomycorrhizal fungi and a fluctuation of the climate sensitivity, which would have dynamically changed on geological time scales, whereas an increase in non-CO2 greenhouse gases could explain the CO2 difference in the Eocene warming.

Co2ncrete: Capturing Carbon dioxide to Create Concrete

As carbon emissions continue to rise and cause the planet to warm up, we need to find ways to reduce them. Capturing carbon at the source of its emission is one of the solutions, but there is still the problem of storing all the carbon sucked out of the atmosphere. If that captured carbon could be put to good use, then perhaps we could have the perfect capturing system in place. This is the line of thinking that researchers at University of California (UCLA) are currently pursuing, and they have some big plans for all that carbon: turning it into concrete.

The conversion of carbon into concrete would be a double whammy since concrete production itself is very planet-unfriendly and accounts for 5 percent of all carbon emissions. But an even larger source of CO2 emissions is flue gas, the combustion exhaust gas from power plants, the scientists' main target.

The carbon would be captured and become the raw material for what they call Co2ncrete, using 3D printers in its fabrication. The researchers describe the multi-stage, complex process, which they are still developing, as upcycling.

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Antarctic ice sheet sensitivity to atmospheric CO2 variations in the early to mid-Miocene

Antarctic ice sheet sensitivity to atmospheric CO2 variations in the early to mid-Miocene

Authors:

Levy et al

Abstract:

Geological records from the Antarctic margin offer direct evidence of environmental variability at high southern latitudes and provide insight regarding ice sheet sensitivity to past climate change. The early to mid-Miocene (23–14 Mya) is a compelling interval to study as global temperatures and atmospheric CO2 concentrations were similar to those projected for coming centuries. Importantly, this time interval includes the Miocene Climatic Optimum, a period of global warmth during which average surface temperatures were 3–4 °C higher than today. Miocene sediments in the ANDRILL-2A drill core from the Western Ross Sea, Antarctica, indicate that the Antarctic ice sheet (AIS) was highly variable through this key time interval. A multiproxy dataset derived from the core identifies four distinct environmental motifs based on changes in sedimentary facies, fossil assemblages, geochemistry, and paleotemperature. Four major disconformities in the drill core coincide with regional seismic discontinuities and reflect transient expansion of grounded ice across the Ross Sea. They correlate with major positive shifts in benthic oxygen isotope records and generally coincide with intervals when atmospheric CO2 concentrations were at or below preindustrial levels (∼280 ppm). Five intervals reflect ice sheet minima and air temperatures warm enough for substantial ice mass loss during episodes of high (∼500 ppm) atmospheric CO2. These new drill core data and associated ice sheet modeling experiments indicate that polar climate and the AIS were highly sensitive to relatively small changes in atmospheric CO2 during the early to mid-Miocene.

Potentially NO Aptian and Albian Cretaceous Atmospheric CO2 changes during oceanic anoxic events

Aptian and Albian atmospheric CO2 changes during oceanic anoxic events: Evidence from fossil Ginkgo cuticles in Jilin Province, Northeast China

Authors:

Sun et al

Abstract:

The Early Cretaceous was a time with super-greenhouse conditions and episodic global oceanic anoxic events. However, relative timing of atmospheric CO2 emissions and oceanic anoxic events, and their causal relationships remain matters of debate. Using the stomatal index approach, well-preserved fossil cuticles of Ginkgo from the Lower Cretaceous Changcai Formation, eastern Jilin, and from the Lower Cretaceous Yingcheng Formation, central Jilin, Northeast China, were investigated to reconstruct atmospheric CO2 concentrations during the Aptian and earliest Albian (Early Cretaceous). The results indicate that the CO2 concentrations reached 1098–1142 ppmv (Carboniferous standardization) or 970–1305 ppmv (regression function) during the Aptian and earliest Albian. Our estimates of palaeoatmospheric CO2 concentrations during the earliest Albian (OAE 1b) are slightly higher than the data between the early Aptian Selli (OAE 1a) and the middle Aptian Fallot OAEs; this may indicate the absence of any great emissions of CO2 during the latest Aptian and earliest Albian.

Estimating Carbon dioxide Levels From the Early Cretaceous

Atmospheric palaeo-CO2 estimates based on the carbon isotope and stomatal data of Cheirolepidiaceae from the Lower Cretaceous of the Jiuquan Basin, Gansu Province

Authors:

Du et al

Abstract:

The stable carbon isotope compositions and the stomatal parameters (stomatal density and stomatal index) of four Cheirolepidiaceae species, Brachyphyllum ningxiaensis, Brachyphyllum obtusum, Pseudofrenelopsis dalatzensis and Pseudofrenelopsis gansuensis, were analyzed to recover the late Early Cretaceous atmospheric CO2 levels. The fossil plants were collected from 5 consecutive sedimentary members of the uppermost Zhonggou Formation. Based on the stomatal data, the estimated palaeo-atmospheric CO2 concentrations in the Jiuquan Basin during the late Early Cretaceous were 1060–882 ppmv based on the carboniferous standardization and were 641–531 ppmv based on the recent standardization; the pCO2 values present at first a decreasing and then an increasing trend within the sedimentary time of the five members. The δ13Cp values based on the 21 Brachyphyllum specimens showed a large variation, which ranged from −20.98‰ to −25.69‰, with an average of −24.2‰. The values also identified a C3 photosynthetic pathway for the Brachyphyllum specimens. The predicted δ13Ca values varied from −2.1‰ to −6.38‰, with an average of −5.03‰. These two proxies were irregular within the different members; therefore, the correlation with the change in atmospheric CO2 concentrations was not significant. Moreover, a water-stressed environment was proposed based on the δ13C values of the present fossil plants, a proposal that was also supported by the previous palaeobotanical, palynological and stratigraphical evidence. In the present study, an inconsistent relationship between the stable carbon isotope and the stomata values was apparent, which most likely indicated that the stomata numbers of the plant were more sensitive to the variation in the concentration of the atmospheric CO2, whereas the δ13C values were sensitive to the moisture conditions.

The Importance of Atmospheric Carbon in the end of the Last Glaciation

As the Earth emerged from its last ice age several thousand years ago, atmospheric carbon dioxide increased and further warmed the planet. Scientists have long speculated that the primary source of this CO2 was from the deep ocean around Antarctica, though it has been difficult to prove.

A new study published this week in Proceedings of the National Academy of Sciences confirmed that the ocean played a significant role in the rise of atmospheric carbon dioxide, but also documents the signature of land-based carbon sources in Antarctic ice cores that contributed to abrupt increases in CO2.

"There wasn't a steady rate of rising carbon dioxide during the last deglaciation," said Edward Brook, an Oregon State University paleoclimatologist and co-author on the PNAS study. "It happened in fits and starts. With the new precise techniques we developed to fingerprint the sources, it is apparent that the early carbon largely came from the ocean, but we think the system got a jolt from an influx of land-based carbon a few times as the climate warmed."

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Human Caused Global Warming has Postponed the Next Glacial Cycle by at Least 50,000 Years

Humanity has become a geological force that is able to suppress the beginning of the next ice age, a study now published in the renowned scientific journal Nature shows. Cracking the code of glacial inception, scientists of the Potsdam Institute for Climate Impact Research found the relation of insolation and CO2 concentration in the atmosphere to be the key criterion to explain the last eight glacial cycles in Earth history. At the same time their results illustrate that even moderate human interference with the planet's natural carbon balance might postpone the next glacial inception by 100.000 years.

"Even without man-made climate change we would expect the beginning of a new ice age no earlier than in 50.000 years from now - which makes the Holocene as the present geological epoch an unusually long period in between ice ages," explains lead author Andrey Ganopolski. "However, our study also shows that relatively moderate additional anthropogenic CO2-emissions from burning oil, coal and gas are already sufficient to postpone the next ice age for another 50.000 years. The bottom line is that we are basically skipping a whole glacial cycle, which is unprecedented. It is mind-boggling that humankind is able to interfere with a mechanism that shaped the world as we know it."

For the first time, research can explain the onset of the past eight ice ages by quantifying several key factors that preceded the formation of each glacial cycle. "Our results indicate a unique functional relationship between summer insolation and atmospheric CO2 for the beginning of a large-scale ice-sheet growth which does not only explain the past, but also enables us to anticipate future periods when glacial inception might occur again," Ganopolski says.

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How Coastal Marshes Respond to Increased Atmospheric Carbon dioxide

Spatial response of coastal marshes to increased atmospheric CO2

Authors:

Ratliff et al

Abstract:

The elevation and extent of coastal marshes are dictated by the interplay between the rate of relative sea-level rise (RRSLR), surface accretion by inorganic sediment deposition, and organic soil production by plants. These accretion processes respond to changes in local and global forcings, such as sediment delivery to the coast, nutrient concentrations, and atmospheric CO2, but their relative importance for marsh resilience to increasing RRSLR remains unclear. In particular, marshes up-take atmospheric CO2 at high rates, thereby playing a major role in the global carbon cycle, but the morphologic expression of increasing atmospheric CO2 concentration, an imminent aspect of climate change, has not yet been isolated and quantified. Using the available observational literature and a spatially explicit ecomorphodynamic model, we explore marsh responses to increased atmospheric CO2, relative to changes in inorganic sediment availability and elevated nitrogen levels. We find that marsh vegetation response to foreseen elevated atmospheric CO2 is similar in magnitude to the response induced by a varying inorganic sediment concentration, and that it increases the threshold RRSLR initiating marsh submergence by up to 60% in the range of forcings explored. Furthermore, we find that marsh responses are inherently spatially dependent, and cannot be adequately captured through 0-dimensional representations of marsh dynamics. Our results imply that coastal marshes, and the major carbon sink they represent, are significantly more resilient to foreseen climatic changes than previously thought.

Dry Ice Causing Martian Channel Creation?

Identification of Mars gully activity types associated with ice composition

Authors:

Vincendon et al

Abstract:

The detection of geologically recent channels at the end of the twentieth century rapidly suggested that liquid water could have been present on Mars up to recent times. A mechanism involving melting of water ice during ice ages in the last several million years progressively emerged during years following the first observations of these gullies. However, the recent discovery of current activity within gullies now suggests a paradigm shift where a contemporary CO2 ice-based and liquid water-free mechanism may form all gullies. Here we perform a survey of near-infrared observations and construct time sequences of water and CO2 ice formation and sublimation at active gully sites. We observe that all major new erosive features such as channel development or lengthening systematically occur where and, if applicable, when CO2 ice is observed or probable. CO2 ice layers are however estimated to be only 1 mm to 1 cm thick for low-latitude sites, which may have implication for potential formation mechanisms. We also observe that part of current gully activity, notably the formation of some new deposits, is poorly compatible with the presence of CO2 ice. In particular, all new bright deposits reported in the literature have a low CO2 ice probability while water ice should be present at most sites. Our results confirm that CO2 ice is a key factor controlling present-day channel development on Mars and show that other mechanisms, potentially involving sublimation or melting of water ice, are also contributing to current gully activity.

Increased CO2 in 20th Century Atmosphere Changed Photosynthesis

Researchers at Umeå University and the Swedish University of Agricultural Sciences have discovered that increasing levels of CO2 in the atmosphere have shifted photosynthetic metabolism in plants over the 20th century. This is the first study worldwide that deduces biochemical regulation of plant metabolism from historical specimens. The findings are now published in the leading journal PNAS and will have an impact on new models of future CO2 concentration in the atmosphere.

In most plants, the uptake of CO2 through photosynthesis is reduced by a side reaction called photorespiration. The research group has now found that the CO2 increase in the atmosphere over the 20th century has shifted the balance between photosynthesis and photorespiration toward photosynthesis. This shift has so far contributed to the global vegetation's ability to dampen climate change by absorbing a third of human-caused CO2 emissions. The photorespiration pathway is known to increase with temperature, which means that temperature and CO2 effects predictably oppose one another. This implies that the CO2 -driven metabolic shift will be counteracted by future temperature increases.

Vegetation's ability to capture CO2 from the atmosphere through photosynthesis is not only a decisive factor for the global CO2 balance but also in predicting future climate change and crop productivity. By monitoring plant metabolism retrospectively using historic plant samples, this research group has quantified how much increased atmospheric CO2 levels during the 20th century have contributed to plants' ability to capture the greenhouse gas carbon dioxide.

"Until recently, studying how plants respond to increases in CO2 on decadal to centennial time scales has relied on simulations based on short-term experiments, because methods to detect long-term metabolic changes were not available. By reconstructing past metabolic shifts in response to environmental changes, we lay the foundation for better modelling of future plant performance," says Jürgen Schleucher, professor at the Department of Medical Biochemistry and Biophysics at Umeå University, who led the study.

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Was Atmospheric Carbon dioxide Capped at 1000 ppm Since the Beginning of the Permian?

Was atmospheric CO2 capped at 1000 ppm over the past 300 million years?

Authors:

McElwain et al

Abstract:

Atmospheric carbon dioxide concentration has shifted dynamically over the Phanerozoic according to mass balance models and the majority of proxy estimates. A new paleo-CO2 proxy method underpinned by mechanistic understanding of plant stomatal, isotopic and photosynthetic responses to CO2 has provocatively claimed that maximum paleoatmospheric CO2 was capped at 1000 ppm for the majority of the past 300 million years. Here we evaluate the robustness of the new paleo-proxy CO2 model by testing its sensitivity to initial parameterization and to scaling factors employed to estimate paleophysiological function from anatomical and morphological traits. A series of sensitivity analyses find that the model is robust to modification in some of the constants employed, such as CO2 compensation point and mesophyll conductance, resulting in variability in paleo-CO2 estimates which are already accounted for in the error propagation of the model. We demonstrate high sensitivity in the model to key input parameters such as initial fossil plant assimilation rate, termed A0 and scaling factors used to estimate stomatal conductance from measurements of fossil stomata. Incorrect parameterization of A0 has resulted in under estimation of pCO2 by as much as 600 ppm. Despite these uncertainties, our analysis highlights that the new mechanistic paleo-CO2 proxy of Franks et al. (2014) has significant potential to derive robust and more accurate CO2 estimates from fossil plant stomata, as long as parameterization of A0 is strongly justified with species appropriate morphological and anatomical data. We highlight methods that can be used to improve current estimates of fossil plant assimilation rates, reduce uncertainty associated with implementation of the Franks et al. (2014) model and importantly add to understanding of patterns of plant productivity over the Phanerozoic, for which there currently is no consensus.

Global Carbon Emissions may Stall, Shrink in 2015

Annual global carbon dioxide emissions from fossil fuels could drop slightly in 2015, according to a report from the Global Carbon Project led by a Stanford University researcher. This surprising result contrasts with the rapid growth in emissions before 2014, underlining the need for action to stabilize and permanently lower global CO2 emissions, the researchers conclude.

"In 2014, global CO2 emissions from burning fossil fuels grew by just 0.6 percent," said lead author Rob Jackson, a professor of Earth system science at Stanford. "This year we expect total emissions to flatten or drop slightly, despite strong growth in gross domestic product worldwide."

While CO2 emissions have slowed during times of economic recession, this would be the first decline during a period of strong global economic growth, Jackson said.

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SURPRISE! Coccolithophores, Calcium Shelled Plankton, Actually Grow MORE With Increased Carbon dioxide, NOT Less

Coccolithophores--tiny calcifying plants that are part of the foundation of the marine food web--have been increasing in relative abundance in the North Atlantic over the last 45 years, as carbon input into ocean waters has increased. Their relative abundance has increased 10 times, or by an order of magnitude, during this sampling period. This finding was diametrically opposed to what scientists had expected since coccolithophores make their plates out of calcium carbonate, which is becoming more difficult as the ocean becomes more acidic and pH is reduced.

These findings were reported in the November 26th edition of Science and based on analysis of nearly a half century of data collected by the long-running Sir Alister Hardy Foundation (SAHFOS) Continuous Plankton Recorder sampling program.

"The results show both the power of long-term time-series of ocean observations for deciphering how marine microbial communities are responding to climate change and offer evidence that the ocean garden is changing," said Dr. William Balch, senior research scientist at Bigelow Laboratory for Ocean Sciences and a co-author of the paper. "We never expected to see the relative abundance of coccolithophores to increase 10 times in the North Atlantic over barely half a century. If anything, we expected that these sensitive calcifying algae would have decreased in the face of increasing ocean acidification (associated with increasing carbon dioxide entering the ocean from the burning of fossil-fuels). Instead, we see how these carbon-limited organisms appear to be using the extra carbon from CO2 to increase their relative abundance by an order of magnitude.

"This provides one example on how marine communities across an entire ocean basin are responding to increasing carbon dioxide levels. Such real-life examples of the impact of increasing CO2 on marine food webs are important to point out as the world comes together in Paris next week at the United Nations Conference on Climate Change," Balch added.

"Something strange is happening here, and it's happening much more quickly than we thought it should," said Anand Gnanadesikan, associate professor in the Morton K. Blaustein Department of Earth and Planetary Sciences at Johns Hopkins and one of the study's five authors.

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Britain to Close Last Coal Power Plant by 2025

The UK's remaining coal-fired power stations will be shut by 2025 with their use restricted by 2023, Energy Secretary Amber Rudd has proposed.

Ms Rudd wants more gas-fired stations to be built since relying on "polluting" coal is "perverse".

Only if gas-fuelled power can fill the void created by closing coal-powered stations would coal plants be shut, she said.

Environmentalists are concerned little is being done to promote renewables.

Announcing the consultation, Ms Rudd said: "Frankly, it cannot be satisfactory for an advanced economy like the UK to be relying on polluting, carbon-intensive 50-year-old coal-fired power stations.

"Let me be clear: this is not the future.

"We need to build a new energy infrastructure, fit for the 21st century."

Former US vice president Al Gore, an active campaigner for clean energy, described the announcement as an "excellent and inspiring precedent".

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