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To weather the worsening drought, California needs healthy soils

By Ellie Cohen, The Climate Center, and Torri EstradaCarbon Cycle Institute

This opinion piece was originally published on February 11, 2021 in CalMatters.

California is in the early stages of a severe multi-decadal drought, exacerbated by the climate crisis. As Dan Walters pointed out in his recent op ed, we must move quickly to prepare for water shortages and wildfires.

A potent strategy to improve the state’s water storage capacity involves an ancient technology so ubiquitous that it is often overlooked: soil. The urgency of California’s drought and wildfire risks require that we invest in soil health now. Demand action.

California is an agricultural powerhouse in large part due to its fertile soils. But historical agricultural practices have depleted their organic carbon content and diminished their water holding capacity. When soil’s carbon is restored through regenerative agriculture, it absorbs and retains more water, restores aquifers, draws down and stores more carbon from the atmosphere, sustains biodiversity, yields more and healthier crops, and increases farm profitability.

The ability of carbon-rich soils to store water and be more resilient to drought and extreme weather is well-documented. For every 1% increase in soil organic matter (a key indicator of soil health), an acre stores an estimated 20,000 gallons of additional water. In one experiment, covering the soil surface with a mulch of crop residue, a regenerative practice that protects soil and reduces evaporation, resulted in a 29% reduction in crop irrigation needs compared to uncovered soil. Another study found that covering soil increased its water retention by 74%.

Compost by Karen Preuss

Compost by Karen Preuss

In California, applying compost to soil has been shown to significantly increase water holding capacity and carbon sequestration on rangelands, and is a recommended practice by public resource management agencies. Combining compost application with cover crops boosts carbon sequestration on croplands.

Restoring soil health is a vital component of a climate agenda to ensure a livable climate for future generations. Nearly every climate modeling scenario that limits warming to 1.5 degrees Celsius includes carbon sequestration with soils. Globally, soils have lost about 135 billion tons of carbon. If this process were reversed – taking carbon out of the atmosphere and storing it in soil – about 14 years of our global carbon footprint would be negated. Worldwide, soil carbon sequestration could remove 110 parts per million of carbon dioxide from the atmosphere over 50 years, studies show.

Soil health makes good business sense. When soils’ natural functions are restored, they require less fertilizer, pesticide, and chemical inputs. As such inputs shrink, costs fall. At the same time, increased resilience of soil means that crop yields are less variable from year to year. All this is good for farmers’ bottom line.

Improving soil health can improve the resilience of rural farming communities, many of which dwell at the margins of economic viability. Case studies of two California almond farms, Okuye and Rogers, found that after adoption of soil health practices, their net income increased by $657 and $991 per acre, respectively, providing a vital boost to these farmers’ livelihoods.

Action is needed now to provide farmers, ranchers, and other land managers with the support they need. We call on California policymakers to:

  1. Rapidly and significantly increase funding for soil restoration by significantly increasing investments in current efforts such as the Healthy Soils Program and by developing new initiatives to meet the growing demand.
  2. Establish an ambitious and urgently needed target for nature-based sequestration on natural and working lands to 100 million metric tons of carbon dioxide equivalent or an amount of sequestration greater than emissions by 2030 annually in California.

Demand action from your policymakers today.

As the science and climate reality require, California must not only cut emissions further and faster but also start now drawing down emissions we have already dumped into the atmosphere using nature-based approaches, while also providing multiple additional benefits.

To reduce worsening droughts, wildfires, and other devastating climate impacts, it is time for state leaders to step up and take bold action. Improving the health of our soils is key to securing a climate-safe future for all.

Endorse Climate-Safe California today and support our work.

New studies show drought and heat waves will kill most trees alive today

By Bob Berwyn, Insideclimate News


Highlights

  • Tim Brodribb, a plant physiologist at the University of Tasmania, published a study that helps identify how trees succumb to heat and dryness
  • The study shows that if climate change continues to persist, most living trees will not be able to survive the warmer climate of the Earth in 40 years
  • Though other research has concluded that more carbon dioxide would result in more plant growth, the negative impacts of warming and drying are already outpacing the fertilization benefits of increased carbon dioxide.
  • Bridribb says the time for action is now:

“We’re at a point where we can see the process, we can predict it. It’s time to start making some noise about it. We can’t afford to sit on our hands.”

  • Since more droughts and higher temperatures are expected, forests globally will continue to be severely impacted with tree deaths
  • The decimation of forests would result in more carbon dioxide in the atmosphere, causing an increase in warming, as well as a loss of animal habitats
  • This new information could damper efforts to plant more trees as a method to sequester carbon since it may become too hot for seeds to sprout 
  • Trees that have survived climate changes and bug infestations will be important in creating new resilient forests

Implementing bold and equitable policies that will catalyze carbon sequestration through building healthy soils and restoring healthy habitats will be key to achieving carbon neutrality by 2030 and net negative emissions by 2035. Endorse The Climate Center’s Climate-Safe California Platform today.


Read more: https://insideclimatenews.org/news/24042020/forest-trees-climate-change-deforestation?

Historic ‘megadrought’ underway in California, American West, new study finds

By Paul Rogers, The Mercury News


Highlights

Nine Western US states have been experiencing an extended mass drought, called a “megadrought.” 

  • Scientists studied over 30,000 tree rings to determine the amount of rainfall and soil moisture over the centuries. The West’s last extended drought period was between 1576 and 1603 and the 20th century was the wettest century though this record
  • Though the megadrought is due to natural events, rising temperatures due to climate change are making drought conditions worse
  • Though there are short periods of decent rain and snowpack, they are anomalies within the bigger drought
  • Bill Patzert, a retired oceanographer and research scientist at NASA’s Jet Propulsion Laboratory says the best way to measure whether a drought is over in the West is to look at the level of Lake Mead, which is currently less than half full
  • California should push more water conservation and efficiency measures that were practiced during its 5-year drought as these dry conditions will come back
  • Depletion of groundwater, dry soils, and dying trees are all symptoms of the large drought
  • Without mitigating climate change, the West will experience more severe droughts 

The climate crisis is here now, worse than anticipated, and accelerating, threatening all life. California must step up its climate leadership to avoid increasingly dire consequences and inspire climate action worldwide. Endorse the Climate-Safe California Platform to enact policies that rapidly address the climate crisis.


Read More: https://www.mercurynews.com/2020/04/16/megadrought-underway-in-california-american-west-new-study-finds/

Climate change increasing fire weather days in California; emissions reductions can reverse this

from Environmental Research Letters


Highlights

As the state gets warmer every year due to the effects of climate change, California’s wildfire season is being fueled by offshore winds, dry vegetation, and drought. These fires result in public health risks from smoke and can result in long term energy shutoffs. 

  • Fire Causes
    • Human exposure and vulnerability to fires is due to the encroachment on wildlands for urban and suburban development 
    • Fire suppression in areas that historically experienced low-intensity fires has led to the accumulation of “fuels” that ultimately promote bigger, intense fires
    • The state’s five warmest years on record occurred in 2014-2018, with autumn temperatures rising and precipitation falling
    • Rising temperatures, declining snowpack, and year-round lack of rain are extending the state’s fire season and will continue to do so
    • Though climate change is fueling fire season, over 80% of fires during autumn in California are human-caused
  • Smoke from these wildfires are causing schools and businesses to close to mitigate exposure to dangerous air pollution
  • The climate model analyses in this report suggest that continued climate change will increase the number of days with extreme fire weather by the end of this century
  • However, meeting climate goals set by the Paris Agreement will curb the increase of fire days

Increased air pollution from fires and fossil fuel emissions makes all of us more vulnerable to the current COVID-19 pandemic. With community energy resilience we can ensure that our power is clean and not further contributing to emissions in our communities. For a safe and healthy future for all, endorse the Climate-Safe California Platform to implement scalable solutions that can reverse the climate crisis.


Read more: https://iopscience.iop.org/article/10.1088/1748-9326/ab83a7