Ecology, Climate Change and Related News

Conservation Science for a Healthy Planet

Conservation Science News Mar 3 2016

Leave a Comment

March 3, 2016

Focus of the Week
The Mystery of the Expanding Tropics; Tracking the 2C Limit











NOTE: Please feel free to pass along this news update that has been prepared for
Point Blue Conservation Science
staff.  You can find these news compilations posted on line by clicking here.  


The items contained in this update were drawn from,,,,, and many other online sources. This is a compilation of information available on-line, not verified and not endorsed by Point Blue Conservation Science.  You can receive this news compilation by signing up for the California Landscape Conservation Cooperative  Newsletter or the Bay Area Ecosystems Climate Change Consortium listserve.  You can also email me directly at ecohen at with questions or suggestions. 


For more information on Point Blue, please see



Focus of the WeekThe Mystery of the Expanding Tropics; Tracking the 2C Limit



In their study, Lu and his colleagues found that climate models generally forecast that the outer edge of the Hadley cell will shift because of global warming. But the models predict a much slower rate of tropical expansion than has been seen so far — which has led researchers to suspect that something else is going on.

The mystery of the expanding tropics

As Earth’s dry zones shift rapidly polewards, researchers are scrambling to figure out the cause — and consequences.

Olive Heffernan 02 February 2016 PDF Nature 530, 20–22 (04 February 2016) doi:10.1038/530020a

….Cities that currently sit just outside the tropics could soon be smack in the middle of the dry tropical edge. That’s bad news for places like San Diego, California. “A shift of just one degree of latitude in southern California — that’s enough to have a huge impact on those communities in terms of how much rain they will get,” explains climate modeller Thomas Reichler of the University of Utah in Salt Lake City. Since Fu and his colleagues announced their discovery1 in 2006, many scientists have investigated the tropical bloating and tried to decipher its cause. Explanations range from global warming to ozone depletion or natural cycles that will reverse in the future. And there is little agreement on how quickly the border of the tropics is shifting: estimates run from less than half a degree of latitude per decade to several. At the more extreme end, the change in climate would be like moving London to the position of Rome over the course of a century2, 3, 4, 5. The problem is compounded by lack of consensus on how to define the tropics, which makes it hard for scientists to agree on the extent of the changes.


Nevertheless, researchers investigating this phenomenon agree that it is real. “There’s a big need to be concerned about this issue,” says climate scientist Chris Lucas at the Australian Bureau of Meteorology in Melbourne. That’s because of the possible impacts: some of the world’s most fertile fishing grounds could disappear, global grain production could shrink and biodiversity could suffer….

Some of the changes in the tropics could be a result of global warming. Reichler investigated that possibility in a study6 led by Jian Lu, an Earth systems scientist now at the Pacific Northwest National Laboratory in Richland, Washington. Working with Gabriel Vecchi, a climate scientist with NOAA in Princeton, New Jersey, the researchers looked at climate forecasts to see how warming might affect an atmospheric circulation pattern called the Hadley cell, which transports heat from the warmer parts of Earth towards the cooler regions (see ‘Bulging waistline’).


As part of the Hadley cell, warm, moist air soars skywards above the Equator and cool, dry air tumbles towards Earth at about 30 ° latitude in the Northern and Southern Hemispheres. That downward limb of the Hadley cell helps to create some of the driest deserts on the planet, such as the Kalahari in southern Africa and the Sahara in northern Africa, and it is one of the most common measures of the boundary between the tropics and the drier subtropics. In their study, Lu and his colleagues found that climate models generally forecast that the outer edge of the Hadley cell will shift because of global warming. But the models predict a much slower rate of tropical expansion than has been seen so far — which has led researchers to suspect that something else is going on. ….


On land, biodiversity is also potentially at risk. This is especially true for the climate zones just below the subtropics in South Africa and Australia, on the southern rim of both continents. In southwestern Australia, renowned as one of the world’s biodiversity hotspots, flowers bloom during September, when tourists come to marvel at some of the region’s 4,000 endemic plant species. But since the late 1970s, rainfall there has dropped by one-quarter. The same is true at South Africa’s Cape Floristic Province, another frontier known for its floral beauty. “This is the most concrete evidence we have of tropical expansion,” says Steve Turton, an environmental geographer at James Cook University in Cairns, Australia.


Turton worries that the rate of change will be too rapid for these ecosystems to adapt. “We’re talking about rapid expansion that’s within half or a third of a human lifetime,” he says. In the worst-case scenario, the subtropics will overtake these ecologically rich outposts and the hotter, drier conditions will take a major toll.…..


But that long wait for an answer will be no comfort for the residents of cities such as Santiago, San Diego and Melbourne, and for the billions of others who live near the boundary between the tropics and subtropics. “We need to understand this issue,” says Lucas, “to have a sustainable civilization there.”







Tracking the 2°C Limit – January 2016

By Rob Honeycutt & Skeptical Science posts: 17 February 2016


January gave us yet another record anomaly in the GISS data, coming in at 1.13C. If we apply this to our preindustrial baseline that puts the monthly anomaly at 1.382C.
(Click here for a full size version of the graph.)….


From posted comments:






  1. Prices have fallen as government incentives have risen….
  2. Demand has expanded, driven partly by public policy….
  3. Corporate and investor support is strong…..


(Pic: Lance Cheung/Flickr)

Solar panel costs set to fall 10% a year

Power from the sun could supply 20% of energy worldwide by 2027 on current technology trends, say UK researchers

By Megan Darby Last updated on 25/01/2016, 5:08 pm

Solar power costs are tumbling so fast the technology is likely to fast outstrip mainstream energy forecasts.
That is the conclusion of Oxford University researchers, based on a new forecasting model published in Research Policy.

Since the 1980s, panels to generate electricity from sunshine have got 10% cheaper each year. That is likely to continue, the study said, putting solar on course to meet 20% of global energy needs by 2027.
By contrast, even in its “high renewable” scenario, the International Energy Agency assumes solar panels will generate just 16% of electricity in 2050. Its widely cited future energy scenarios in previous years failed to predict solar’s rapid growth.
Mathematics professor Doyne Farmer, who co-wrote the paper, said the research could help to shape clean energy policy.
“Sceptics have claimed that solar PV cannot be ramped up quickly enough to play a significant role in combatting global warming,” he said.
“In a context where limited resources for technology investment constrain policy makers to focus on a few technologies… the ability to have improved forecasts and know how accurate they are should prove particularly useful.”…


California Narrowly Votes to Retain System That Pays Solar Users for Excess Power

By DIANE CARDWELL NY Times January 28, 2016

The California Public Utilities Commission agreed to retain a system that pays users of rooftop solar panels a retail rate for the electricity they return to the grid….


SolarReserve’s breakthrough Crescent Dunes solar tower with thermal storage has successfully generated electricity at its full 110 MW capacity.

Crescent Dunes 24-Hour Solar Tower Is Online

February 22nd, 2016 by Susan Kraemer 

With this milestone achieved, the CSP (Concentrated Solar Power) project has now passed the necessary test to begin full commercial operation under its 25-year Power Purchase Agreement (PPA) with NV Energy to supply power well into the night for Las Vegas and other parts of Nevada. The molten salt receiver actually exceeded design expectations, SolarReserve CEO Kevin Smith told CleanTechnica. The heat transfer efficiency of the receiver is the key performance validation of SolarReserve’s patented solar thermal storage technology. “We are meeting 100% of our requirements so far. The technology has been fully proven,” said Smith. “There’s additional testing that our EPC; ACS Cobra has to do on the balance of the plant and once that is complete in the next few weeks, we start to ramp up our annual output.” Under the rollout plan with NV Energy, Crescent Dunes will now begin its official ramp-up over the coming year, with generation increasing gradually each month…


Going green can add value to your home.
January 27, 2016 Washington Post

What is going “green” worth in Washington home real estate? A new study conducted by national appraisal experts says energy improvements and resource-conserving efforts can be worth tens of thousands of dollars….


Todd Griffith shows a cross-section of a 50-meter blade, which is part of the pathway to the 200-meter exascale turbines being planned under a DOE ARPA-E-funded program. The huge turbines could be the basis for 50-megawatt offshore wind energy installations in the years ahead. Credit: Photo by Randy Montoya

Enormous blades could lead to more offshore energy in US [What about seabirds and other marine wildlife?Ellie]

Posted: 28 Jan 2016 10:32 AM PST

A new design for gigantic blades longer than two football fields could help bring offshore 50-megawatt (MW) wind turbines to the United States and the world. Sandia National Laboratories’ research on the extreme-scale Segmented Ultralight Morphing Rotor (SUMR) is funded by the Department of Energy’s (DOE) Advanced Research Projects Agency-Energy program. The challenge: Design a low-cost offshore 50-MW turbine requiring a rotor blade more than 650 feet (200 meters) long, two and a half times longer than any existing wind blade. The team is led by the University of Virginia and includes Sandia and researchers from the University of Illinois, the University of Colorado, the Colorado School of Mines and the National Renewable Energy Laboratory. Corporate advisory partners include Dominion Resources, General Electric Co., Siemens AG and Vestas Wind Systems. “Exascale turbines take advantage of economies of scale,” said Todd Griffith, lead blade designer on the project and technical lead for Sandia’s Offshore Wind Energy Program.





Ellie Cohen, President and CEO

Point Blue Conservation Science

3820 Cypress Drive, Suite 11, Petaluma, CA 94954

707-781-2555 x318  | Follow Point Blue on Facebook!

Point BlueConservation science for a healthy planet.



View all articles

Leave a Reply

Your email address will not be published. Required fields are marked *