A friend in Sonoma sent this excellent document/ You can download the original or read below


The target date that we set for city-wide “carbon-neutrality” (or “net zero emissions”) is of utmost importance.

Current California laws require a 40% reduction in greenhouse gas (GHG) emissions below 1990 levels by 2030 (SB32) and an 80% reduction by 2050 (Executive Order S-3-05). These laws imply a zero emissions target date of around 2060.

Governor Brown’s more recent (2018) Executive Order B-55-18 sets a goal of “…carbon neutrality as soon as possible and no later than 2045.” (The target is often misrepresented as 2045; “as soon as possible” really means “as soon as possible!”) The City of Petaluma’s May 2019 Climate Emergency Resolution committed the City to this same timeframe.

The 2018 IPCC Special Report on Global Warming of 1.5degC(Note 1) stated that we had 20 years (until 2038) to reach carbon neutrality in order to have “a two-thirds chance of limiting warming to 1.5degC.” The Report adds that “…geophysical uncertainty … translates into a variation of this timing … of roughly 15 to 20 years.” Geophysical uncertainty refers to the effect of amplifying feedback loops such at the release of methane due to melting permafrost, the “ice albedo effect,” and others.

Thus, according to the IPCC, our target date for zero emissions – and for limiting warming to 1.5oC — may already have passed.

Note 1 IPCC Special Report on Global Warming of 1.5oC, Chapter 2, p. 96.

Amplifying feedback loops trigger climate “tipping points” that are irreversible within the scale of human lifetimes. Not surprisingly, these uncertainties are not playing out in our favor. Mounting scientific evidence documents climate effects, such as the melting of ice sheets in Antarctica and Greenland, proceeding far faster than recent climate models had predicted.

In addition, it’s important to put the IPCC projections into context: IPCC reports represent the consensus opinion of the world’s leading climate scientists and must be reviewed and approved by the governments of over 100 nations prior to publication. In other words, IPCC reports express conservative scientific consensus tempered by political reality. As dire as their warnings may seem, they err on the side of optimism.

No rational person would board an airplane or an elevator that had only a two-thirds chance of arriving safely at its destination. And yet, with regard to the climate crisis, we’re asking people to take such a risk.

In the realms of engineering design, insurance underwriting, disaster preparedness, and others, where concern for human health and safety is paramount, we don’t prepare for “likely” (i.e., high-probability) scenarios. Instead, we identify and prepare for worst-case (i.e., lowprobability) scenarios. In these realms, we seek to reduce the probability of disaster to 0.1% or 0.01% or less.

If we were to apply the same level of concern for human health and safety in addressing the climate crisis, we would immediately cease all GHG emissions.


As a compromise between the exigencies of the climate crisis and political reality, we are calling for a target date for net zero emissions of 2030. Net zero emissions – as opposed to true zero emissions – allows for emissions to be offset by sequestration, carbon offsets, or similar accounting measures. Our 2040 goal is true zero emissions.

Finally, it’s worth noting that a zero emissions world is a highly desirable place to live. Eliminating fossil fuels and all the other greenhouse gases yields a multitude of benefits:

  1. • Cleaner air and water
  2. • Lower utility costs
  3. • More nutritious food
  4. • A more active population
  5. • Lower healthcare costs
  6. • Less traffic
  7. • Fewer traffic accidents
  8. • A greater sense of community

The Climate Center (formerly the Center for Climate Protection), the leading climate mitigation advocate in Sonoma County for well over 15 years, is calling for “…net negative emissions by 2030.” Net negative emissions is a step beyond net zero emissions.

The following is a sampling of the entities that have set a target date of 2030 (or sooner) for net zero emissions or carbon neutrality:

Entity Target date

  • Norway 2030
  • Uruguay 2030
  • Church of England 2030
  • Adelaide, Australia 2025
  • Melbourne, Australia 2020
  • Copenhagen, Denmark 2025
  • Birmingham, England 2030
  • Bristol, England 2030
  • Liverpool, England 2030
  • Oslo, Norway 2030
  • Asheville, NC 2030
  • Burlington, VT 2030
  • Montpelier, VT 2030
  • Chico, CA 2030
  • Hoboken, NJ 2027
  • Sacramento, CA 2030
  • Portland, ME 2030
  • Worcester, MA 2030
  • Los Angeles, CA 2030
  • UC System 2025
  • Over 700 B Corps 2030
  • Microsoft 2030

In addition, two of our neighbors in Sonoma County passed Climate Emergency Resolutions that clearly state a 2030 target date for net zero emissions. They are:

  • Santa Rosa: “…with the goal of reaching carbon neutrality by 2030.”
  • Sebastopol: “…reducing city-wide greenhouse gas emissions to net zero by no later than 2030”

And our Sonoma County Regional Climate Protection Authority (RCPA) has pledged to produce a countywide 2030 Climate Emergency Mobilization Strategy although a clear target date has not been established.

And a closing comment:

Just as a mother will spare no effort to protect her child, so must we do everything in our power to ensure a stable climate for all beings and all life. The work ahead of us at times seems impossible. But impossible is not a fact; it is a challenge.

We quote from the recently-published report titled Vision for Equitable Climate Action released by the U.S. Climate Action Network:

“There is lively, ongoing debate about the maximum achievable rate of emissions reductions. In the U.S., a 2030 target of 100% reductions would be ideal, but many experts think it is simply not possible. We should strive toward that goal but, given that authoritative voices are arguing that domestic carbon dioxide emissions can be reduced as much as 70% by 2030, we believe this is an appropriate target and should be coupled with commensurate annual targets…” [p.6]

Let us set our sights high.