Environment

6 charts from new report show how much California’s climate has already changed

See how sea-level rise could affect the San Francisco Bay Area

The San Francisco Bay Area is one of the most vulnerable parts of California to sea level rise. See how the bay would expand during high tide under different scenarios.
Up Next
The San Francisco Bay Area is one of the most vulnerable parts of California to sea level rise. See how the bay would expand during high tide under different scenarios.

Warmer days — and nights. Rising sea levels. Less water available in summer.

A report released Wednesday by state officials says climate change is affecting California’s ecosystem already in ways great and small.

The document looks at 36 indicators that measure aspects of climate change, including human-influenced causes of climate change such as greenhouse gas emissions and the impact of the changes on people and wildlife.

The report is the third assessment of climate change's effects in the past nine years by the California Environmental Protection Agency and the Office of Environmental Health Hazard Assessment.

The latest effort shows “some of the trends are continuing, some of the trends are accelerating,” said spokesman Sam Delson of the health hazard office. Here are a few examples:

Annual average air temps rising

Since 1895, annual average air temps have increased throughout the state, rising at a faster rate beginning in the 1980s.
Average air temps in California from 1890 to 2017
Source: Western Region Climate Center


Average nightly low temperatures rising

Average decadal nightly lows and average decadal highs are rising relative to the long-term average temperature based on data from 1949 to 2005. Night temps have increased at a rate of 2.3°F per century, compared to 1.3°F per century for day high temps.
Average nightly low temps and day highs in California from 1900 to 2017
Source: Western Region Climate Center


Sacramento River spring runoff

Snowmelt runoff into the Sacramento River between April and July relative to total year-round water runoff has declined over the past century.
Sacramento River spring runoff charted from 1905 to 2017
Source: Department of Water Resources 2016, updated 2017


Shrinking glaciers in the Sierra

From the beginning of the 20th century to 2014, some of the largest glaciers in the Sierra have lost an average of about 70 percent of their area.
Historical and contemporary photographs of the Dana Glacier in the Sierra

Sea level creeping up

Along the California coast, mean sea levels have generally risen. Since 1900, mean sea level has increased by about 180 millimeters (7 inches) at San Francisco.
Mean sea levels at San Francisco rising from 1900 to 2017
*Relative to a tidal reference point set by NOAA


Wildfires

The area burned by wildfires each year has been increasing since 1950. Five of the largest fire years have occurred since 2006.
Annual acres burned by wildfires in California
Source: CalFire, 2018

  Comments