Climate Change

Our Warming Climate

The air temperature around the world is warming, which creates problems for Southern Residents and their primary food–salmon.

For thousands of years before 1950, the amount of carbon dioxide in the air was below 300 parts per million.¹ But as the number of humans grew, so did the number of cars and trucks, the amount of electricity generated, and the number of industries–all of which put more carbon dioxide in the air. Today, there are 405 parts per million of carbon dioxide in the air, which has raised the global air temperature 1°C.

Scientists predicted the temperature will continue to rise by about 0.2°C each decade.¹ When it grows more than 1.5°C, which scientists project could happen by 2030, the results will be catastrophic and irreversible. The results in Washington would be the following:¹

• 67 percent more days above 90°F
• 38 percent decrease in snowpack
• 16 percent increase in winter stream flow
• 23 percent decrease in summer stream flow

All of these changes would decrease the number of salmon, further decreasing food for Southern Residents. To illustrate, as the temperature warms, it melts the snow on top of the mountains earlier, which means less cool water to feed streams in the summer. Streams will dry up or have water that is too hot for salmon to survive. Warmer water also saps salmon’s energy, makes them more susceptible to disease, impedes their growth, and makes them easier targets for fish and other animals to eat.

Heavier winter storms mean more flooding and more water rushing through streams in the winter, washing away salmon eggs and young fish. Fewer will survive to become adults and feed the orcas.

In addition to warming the air, carbon dioxide is making the oceans more acidic. Oceans have absorbed 25 percent of the carbon dioxide in the air.¹ Carbon dioxide can harm the wildlife that salmon eat and inhibit salmon’s ability to find food and avoid predators.

With fewer salmon to eat, Southern Residents are hungry. As they lose weight, they process more of the metals and toxins stored in their bodies, which increases their chances of disease and neurological problems. In addition, more acidic ocean water spreads out underwater noise making it harder for orcas to find food.^2,3

To read more details about the devastating effects of climate change and what the Governor’s Southern Resident Killer Whale Task Force recommends to slow climate change, see the task force’s final report, page 39.

The task force developed several recommendations for increasing the number of salmon. Learn more about these recommendations and the progress being made.

¹A. K. Snover, C. L. Raymond, H. A. Roop and H. Morgan, “No Time to Waste. The Intergovernment Panel on Climate Change’s Special Report on Global Warming of 1.5C and Implications for Washing State.,” University of Washington Climate Impacts Group, Seattle, WA, 2019
²T. Klinger, “Potential effects of warming and acidification on Southern Resident Killer Whales.,” in Southern Resident Killer Whale Task Force Meeting, Lacey, WA, 2019.
³P. G. Brewer and K. Hester, “Ocean acidification and the increasing transparency of the ocean to low frequency sound,” Oceanography, vol. 22, no. 4, pp. 86-93, 2009.