As an Amazon Associate I earn from qualifying purchases.
Started by Woolly Bugger, November 25, 2022, 12:35:32 PM
0 Members and 1 Guest are viewing this topic.
View this post on Instagram
QuoteLeaf waxes also predate climate records from Antarctic ice cores, which go back only about a million years and require a climate that can support ice. One study used leaf waxes to glimpse the climate of a warmer Spain some 15 to 17 million years ago. Another looked at the moisture history of Southwest Africa for the past 3.5 million years. Bhattacharya began using them while working as a postdoctoral fellow in Tierney's lab. Five years ago, she and Ran Feng, a coauthor, came up with the idea of studying the Pliocene while riding a bus during a conference for young researchers. Their analysis started with marine sediments collected decades ago by the research vessel Joides Resolution, which roams the oceans drilling cores from as deep as 6 miles below the surface. The samples used for the study were taken off the coast of California: one off the Baja peninsula from a depth of more than 2,600 meters, and one from the East Cortes Basin at a depth of 1,700 meters. During the Pliocene, leaf waxes would have been transported west on the wind to become part of this marine sediment. The team got a cube of each core, freeze-dried them, and ran them through "a glorified espresso machine," says Bhattacharya, using a solvent under pressure at high temperatures that extracted the waxes. Then they measured the hydrogen and carbon isotope composition using a gas chromatograph-isotope ratio mass spectrometer, which separated the waxes by their molecular mass. "The hydrogen that's used to make the wax is coming from rainwater that the plant uses to grow. You can think of isotopes as like a fingerprint," Tierney says. "These isotopes actually trace the kind of rainfall you have, which is pretty cool. They can also trace the amount of winter rainfall versus summer rainfall. So, it's pretty powerful."For the second part of the study, climate modeler Ran Feng, a professor at the University of Connecticut's Department of Geosciences, ran simulations to determine how sea temperatures influenced the stronger monsoons of the mid-Pliocene. Feng found that when marine temperatures—in an area that extends from Alaska to off the coast of Baja, California—were higher relative to the usually warmer tropical waters off Central America, they created conditions for stronger monsoons in the Southwest. Warmer local air acts like a heat pump, drawing the relatively cooler tropical air and warming it, pulling in moisture. "So it creates this loop," she says. "That's why this is able to drive moisture into the Southwest North America regions."That kind of marine heat wave has occurred off California in recent years and will become more prevalent as temperatures rise, feeding more intense monsoon storms.
QuoteThis year the American Farmland Trust said that expanding solar power could gobble up as much as 3,900 square miles nationwide, and predicted that many Eastern states could lose between 1.5% and 6% of their undeveloped land to solar facilities – mostly on farmland that's flat, cleared, and near to existing transmission infrastructure. A Princeton University study this year forecast that achieving a net-zero-emissions economy by 2050 could directly impact a cumulative land area the size of Virginia, with forested lands the most directly impacted by solar deployment in Eastern states.
Quote from: Woolly Bugger on March 11, 2023, 16:35:07 PMMapping California's 'Zombie' ForestsA warming climate has left a fifth of the conifer forests that blanket California's Sierra Nevada stranded in habitats that no longer suit them, according to a study published last week by researchers at Stanford University.In these "zombie forests," older, well-established trees — including ponderosa pines, Douglas firs and sugar pines — still tower overhead, but few young trees have been able to take root because the climate has become too warm and dry for them to thrive.Guests are not allowed to view images in posts, please Register or LoginRead the rest; New York Times
Quote from: Trout Maharishi on March 11, 2023, 17:13:53 PMMumbo Jumbo How many man hours and much grant money did it take to figure out this jewel of a scientific information?
Quoteauthor=Onslow link=msg=179211 date=1678582777]I don't think many expected to see the SW become so wet during a La Nina Winter. There is strong certainty an El Nino pattern will set up this Fall, which pretty much ensures California will have a second year of above normal precipitation. Maybe new growth will get a toehold.
Quote from: Mudwall Gatewood 3.0 on March 12, 2023, 14:34:18 PMMore rain/snow is great news, certainly when it comes to wildfires. But is it precipitation or temperature, or both, that is the issue as it pertains to the conifers adapting?
Quote from: Trout Maharishi on March 12, 2023, 17:15:20 PMI am concerned about droughts and fires, and I hope CA and the CAFS has learned some valuable lessons about the value of controlled burns. This is one of the most beautiful places in the world and the trees are magnificent both in size and age. I'm hoping they all continue to thrive for future generations. [/quoteI'm of the opinion that controlled burns are an antiquated forest science and that data has proven that the importance of rotting and decaying trees is way more important to the forest ecosystem and the foundations of the living forest. If naturally occurring fires are a part of the life cycle in a forest, then let them occur naturally. I fear that regular controlled burns may have become a way to justify jobs in the forest service.