Ecosystems and Biodiversity
The impacts of global warming will be far greater than expected, according to the latest comprehensive assessment from the UN’s Intergovernmental Panel on Climate Change. The IPCC’s review of over 6,000 studies concluded that the “safe” limit of 1.5 °Celsius increase could be reached in as little as 12 years and that we are currently on target for a 3° rise by the end of the century. Even a 0.5° C rise will deplete 60 to 70% of coral, while a 2° C rise will decimate 100%. To limit warming to 1.5 ° C requires significant action, like reducing fossil fuels by 50% in under 15 years as well as widespread reforestation to curb carbon emissions. Via National Geographic
Ulva mutabilis, also known as Sea Lettuce, is a fast-growing seaweed that dominates intertidal regions and spawns massive green tides. Recent studies have uncovered some of the reasons behind its successful growth rates. Sea lettuce lives in symbiosis with bacteria and is a gene thief, stealing genetic material that helps the weed adapt to excessive light, high salinity and dehydration. Via Science Daily
There are only 74 individuals remaining in the Southern Resident population of killer whales off the Pacific Northwest and they’ve failed to reproduce successfully in the past three years. But a new initiative hopes to sequence the genome of the endangered killer whales using samples collected from live and dead whales over the past two decades. The information could help explain, for example, whether internal factors such as inbreeding or genetic variation in immune systems are preventing the whales from recovering. The results will be compared to the genomes of the more abundant Alaska population of killer whales, as well as mammal-eating transient whales. The race is on to find the cause behind the dwindling southern resident populations. Via Phys.org
Scientists use biomarker species to detect the small, but profound effects of climate change, as species provide an early warning signal that the environment is stressed before an ecosystem collapses. However, recent climate change-driven shifts are beginning to alter the usefulness of these biomarkers. Organisms migrate to avoid higher temperatures or their behaviour changes as the pH, salinity or temperature changes around them. Scientists are currently monitoring biomarker species to ascertain whether models need to be re-evaluated or new species need to be used to provide these critical early warning systems. Via Independent
A city has a “water footprint” of whats its inhabitants use to grow the food they eat and support their lifestyles. Maps of 65 American cities show that large urban areas have smaller water footprints per citizen than smaller towns, probably because they are more oriented to service industries rather than water-hungry industrial processes. These maps should help city planners understand and predict water consumption more accurately. Via EurekAlert!
Unless it is hopelessly polluted, water is mostly reused. While carbon footprints are valuable, some scientists and industry groups feel that the concept of a water footprint is too simplistic, and that we need to consider wider factors. Such factors could determine whether water is being abstracted from an aquifer at an unsustainable rate, whether irrigation schemes are necessary and properly controlled, and how to balance the needs of all water users in the area. Via The Conversation
Algal cover is considered one of the strongest indicators of coral reef stress. Scientists performed an experiment with sound emissions by recreating the conditions in a tank. The study showed that the gas bubbles- a combination of the oxygen released from the photosynthesis and the nitrogen- turned into a spherical shape and produced a ringing noise. This ringing noise is called “algae noise” and is linked to the abundance of algae in the water. This technique will help estimate algal abundance compared to the costly and time-consuming visual methods of the past. Via Science Daily
The U.S., Russia, Canada, Norway, Denmark, Iceland, Japan, South Korea, China and the EU have signed a pact banning commercial fishing across much of the Arctic for at least 16 years. As Arctic waters warm and sea ice recedes, thee agreement could allow stocks of fish that have been forced out of their traditional grounds, such as cod and halibut, to recover. Via The Guardian
Bangkok is sinking at the rate of 2 centimetres a year, while the surrounding seas are rising faster than the global average. This city of 10 million regularly floods, and now the city planners are working on a suburb built over vast water storage tanks. Floods can be diverted into the underground tanks and used to flush out the sewers as the waters recede. Via The Guardian
A review of over a thousand papers looked at potential solutions to climate change involving the oceans. The conclusion? Governments should pursue offshore wind farms and wave energy to reduce fossil fuel emissions, as well as encouraging mangroves, salt marshes, and coral reefs to soak up carbon. Ideas that seem good, but have significant downsides include seeding the sea with iron to encourage phytoplankton and generating fluffier clouds (or covering the sea with foam) to reflect the sun. Via Wired
Swedish researchers developed a liquid that collects energy from the sun and releases heat on demand, hours or months later. The liquid changes its structure when it absorbs photons and releases it as a burst of heat when passed over a catalyst. Amazingly, the new structure is so stable it can release its energy overnight or be “charged” during summer to release heat during the winter. Via EurekAlert!
If you etch tiny grooves into a silicon substrate and fill them with oil, you end up with an extremely hydrophobic surface that also absorbs electrons. If you then run an ionized liquid, like salt water, over the surface, you can produce an electric current. While it isn’t large, it might provide free energy for specialist applications or even a partial power source for desalination plants. Via EurekAlert!