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Forests. Phytoplankton. Plant Growth Database. Seeing is Believing. The Unstoppable CO2-Induced Greening of the Earth Continues. Study suggests increased atmospheric CO2 created a 30% growth in plant photosynthesis during last two centuries. Composite image showing the global distribution of photosynthesis, including both oceanic phytoplankton and terrestrial vegetation.

Study suggests increased atmospheric CO2 created a 30% growth in plant photosynthesis during last two centuries

Dark red and blue-green indicate regions of high photosynthetic activity in the ocean and on land, respectively. Image: NASA SEAWIFS Research shows global photosynthesis on the rise “Virtually all life on our planet depends on photosynthesis,” said UC Merced Professor Elliott Campbell, who led the research. “Keeping tabs on global plant growth should be a central goal for the human race.” Photosynthesis is the process through which plants use sunlight to convert carbon dioxide (CO2) into carbohydrates to fuel their growth and other activities. Yet, researchers lack a clear picture of global trends in photosynthesis over the past few centuries.

But maybe not for long. “Previous studies covered small physical areas or short periods of time,” Campbell said. Elevated CO2 as a driver of global dryland greening - Principia Scientific International. While recent findings based on satellite records indicate a positive trend in vegetation greenness over global drylands, the reasons remain elusive.

Elevated CO2 as a driver of global dryland greening - Principia Scientific International

We hypothesize that enhanced levels of atmospheric CO2 play an important role in the observed greening through the CO2 effect on plant water savings and consequent available soil water increases. Meta-analytic techniques were used to compare soil water content under ambient and elevated CO2 treatments across a range of climate regimes, vegetation types, soil textures and land management practices. Based on 1705 field measurements from 21 distinct sites, a consistent and statistically significant increase in the availability of soil water (11%) was observed under elevated CO2 treatments in both drylands and non-drylands, with a statistically stronger response over drylands (17% vs. 9%).

To better predict system responses to possible climate changes, it is necessary to understand the drivers behind the observed greening response. Matt Ridley: Global Warming versus Global Greening. The Royal Society, London 17 October 2016 Matt Ridley delivers the 2016 Annual GWPF Lecture at the Royal Society, London 17 October I am a passionate champion of science.

Matt Ridley: Global Warming versus Global Greening

I have devoted most of my career to celebrating and chronicling scientific discovery. I think the scientific method is humankind’s greatest achievement, and that there is no higher calling. So what I am about to say this evening about the state of climate science is not in any sense anti-science. I am still in love with science as a philosophy; I greatly admire and like the vast majority of scientists I meet; but I am increasingly disaffected from science as an institution. Andy May Petrophysicist. By Andy May The Earth’s atmosphere is 78% nitrogen, 21% oxygen and 0.9% argon.

Andy May Petrophysicist

These are not greenhouse gases and they total 99.9%, leaving little space for the greenhouse gases methane, carbon dioxide and water vapor. The amount of water vapor in the atmosphere varies a lot with altitude and temperature. At low altitude and high temperatures (greater than 30°C or 86°F), over the ocean, it can reach 4.3% or more of the atmosphere and is less dense than dry air, causing it to rise. It will rise until the temperature is low enough for it to condense to a liquid or solid state and form clouds, rain or snow. Max Planck Institute (Model Calculations): Sahel Is Greening (Due To Human Activity)! What follows is another example of climate science making up a theory to fit an observation.

Max Planck Institute (Model Calculations): Sahel Is Greening (Due To Human Activity)!

Of course, most of us suspect that natural cycles are what’s really at play here. Elevated CO2 A Key Driver of Global Greening Observations. Paper Reviewed Lu, X., Wang, L. and McCabe, M.F. 2016.

Elevated CO2 A Key Driver of Global Greening Observations

Elevated CO2 as a driver of global dryland greening. Scientific Reports 6: 20716, doi:10.1038/srep20716. Despite continued attempts by alarmists to portray rising atmospheric carbon dioxide (CO2) as a danger and threat to the planet, more and more scientific evidence is revealing nothing could be further from the truth. The latest example to demonstrate such comes from a paper recently published in the journal Scientific Reports, where Lu et al. (2016) investigated the role of atmospheric CO2 in causing the satellite-observed vegetative greening of the planet that has occurred over the past few decades (1960-2015).

It has long been known that rising CO2 boosts plant productivity and growth, and it is equally well-established that increased levels of atmospheric CO2 reduce plant water needs/requirements, thereby improving their water use efficiency. Study: UHI affects the urban growing season. Urban Heat Island profile Image from Lawrence Berkeley Labs From the UNIVERSITY OF WISCONSIN-MADISON Spring comes sooner to urban heat islands, with potential consequences for wildlife Urban-dwelling plants around the globe typically get a head start on the growing season compared to their rural counterparts because of the urban heat island effect, the phenomenon in which cities tend to be warmer than nonurban areas due to their plethora of built surfaces — made of concrete, asphalt and more — and scarcity of vegetation.

Study: UHI affects the urban growing season

But according to the study, published this week in Environmental Research Letters, the urban heat island doesn’t lengthen the growing season uniformly across a city. Within the study site (Madison, Wisconsin) the researchers found that while the growing season lasted up to a week longer in the city’s densest areas, its parks subdued the warming effect and thus helped to normalize the growing season length. Like this: Like Loading... The Future of Coastal Productivity. Paper Reviewed Villafañe, V.E., Valiñas, M.S., Cabrerizo, M.J. and Helbling, E.W. 2015.

The Future of Coastal Productivity

Physio-ecological responses of Patagonian coastal marine phytoplankton in a scenario of global change: Role of acidification, nutrients and solar UVR. Marine Chemistry 177: 411-420. Writing as background for their work, Villafañe et al. (2015) note there is a growing interest in determining the effects and impacts of global change on estuaries, citing the works of Bricker et al. (2008), Bianchi and Allison (2009) and Gillanders et al. (2011), particularly with respect to phytoplankton, given that the tiny plants are responsible for a large share of the primary production in such waters. The results of their investigation revealed that marine phytoplankton were "more efficient" under future than current conditions, regardless of solar radiation treatment. Elevated CO2 Stimulates the Growth of an Aquatic Fern.

Paper Reviewed Van Kempen, M.M.L., Smolders, A.J.P., Bögemann, G.M., Lamers, L.P.M. and Roelofs, J.G.M. 2016.

Elevated CO2 Stimulates the Growth of an Aquatic Fern

Interacting effects of atmospheric CO2 enrichment and solar radiation on growth of the aquatic fern Azolla filiculoides. Freshwater Biology 61: 596-606. Writing as background for their work, van Kempen et al. (2016) note that Azollaceae are among the fastest growing plants in the world and that such free-floating freshwater ferns are utilized and valued "as a green fertilizer in paddy fields," as "a phytoremediation tool for contaminated surface waters and wastewaters, and for the production of biogas and animal food," citing Wagner (1997) and van Hove and Lejeune (2002). Given such application/uses the five Dutch researchers set out to learn how the growth of this species might be affected by rising concentrations of atmospheric CO2 expected to be reached over the course of this century.

Plant responses to low [CO2] of the past - Gerhart - 2010 - New Phytologist. Warming of the Mediterranean causes stronger rainfall in the Sahel. Anthropogenic climate change contributes to fanning of the West African monsoon by moisture from the Mediterranean July 13, 2016 Climate change can have mixed consequences: It would appear that the warming of the Mediterranean region, which has brought greater heat and drought to the countries there for around 20 years, is behind an increase in rainfall in the Sahel region.

Warming of the Mediterranean causes stronger rainfall in the Sahel.

As researchers from the Max Planck Institute for Meteorology in Hamburg report in the current edition of the journal Nature Climate Change, due to higher sea temperatures in the Mediterranean more moisture from the eastern Mediterranean is reaching the southern edge of the Sahara at the start of the West African monsoon in June. Moreover, according to the current study, the future development of precipitation in the Sahel region is crucially dependent on the warming of the Mediterranean. Zoom Image © Daniel Triveau / CIFOR (CC-BY-NC-ND 2.0) Plant Root Loss to Herbivores Reduced by Aerial CO2 Enrichment. Paper Reviewed McKenzie, S.W., Johnson, S.N., Jones, T.H., Ostle, N.J., Hails, R.S. and Vanbergen, A.J. 2016. Root Herbivores Drive Changes to Plant Primary Chemistry, but Root Loss is Mitigated under Elevated Atmospheric CO2.

Frontiers in Plant Science 7: 10.3389/fpls. Writing as background for their work, McKenzie et al. (2016) say that "belowground herbivory represents a major challenge to crop productivity and sustainable agriculture. " And to learn how atmospheric CO2 enrichment might possibly impact this unfortunate situation in the case of the raspberry host-plant (Rubus idaeus), they conducted a microcosm experiment using the large raspberry aphid (Amphorophora idaei) and the root-feeding larvae of the vine weevil (Otiorhynchus sulcatus).

First of all, and rather surprisingly, McKenzie et al. report that the elevated CO2 environment did not increase crop biomass, nor did it impact herbivore abundance. An Inconvenient Truth — Biological Productivity of the Tundra Has Increased Since 1981, Perhaps Due to Warming. Is that a scary thing? Guest post by Indur M. Goklany In its October 14, 2010 issue, Nature magazine (p. 755) reports on a paper by JMG Hudson and G HR Henry, Increased plant biomass in a High Arctic heath community from 1981 to 2008, Ecology 90:2657–2663 (2009). (PDF ) It notes that, based on data collected from study plots over a 13-year period and survey data covering 27 years on the tundra of Ellesmere Island in Nunavut, Canada, an area where both temperatures and the length of the growing season has increased in recent decades:

A 33-Year History of the Productivity of Arctic and Boreal Vegetation. Paper Reviewed Park, T., Ganguly, S., Tommervik, H., Euskirchen, E.S., Hogda, K. -A., Karlsen, S.R., Brovkin, V., Nemani, R.R. and Myneni, R.B. 2016. Changes in growing season duration and productivity of northern vegetation inferred from long-term remote sensing data. Environmental Research Letters 11: 084001. More Evidence that FACE Studies Underestimate the Positive Impacts of CO2 Enrichment on Plant Growth. Paper Reviewed Bunce, J.A. 2016. Responses of soybeans and wheat to elevated CO2 in free-air and open top chamber systems. Field Crops Research 186: 78-85. There is little doubt that nearly all plants respond positively to atmospheric CO2 enrichment, experiencing increases in photosynthesis, biomass and water use efficiency, to name but a few of the most commonly reported benefits. However, the magnitude of the CO2 response has remained a topic of debate given that different values have been derived from different experimental setups.

Primarily, there are two main systems designed for use in CO2 enrichment studies: open top chamber (OTC) and Free-Air-CO2-Enrichment (FACE). FACE systems are also established in natural settings, but are constructed without walls. In general, OTC studies yield CO2-induced growth response increases that are significantly higher than those found in FACE studies.