This Dam Weather

Climate change and energy production are in a kind of twisted embrace. There’s the obvious aspect of it: Much of the energy produced today comes from burning hydrocarbons, which leads to further building up of carbon dioxide into the atmosphere, causing climate change. To fix that, more energy has to be generated from sources that don’t emit carbon.

But here’s the less obvious aspect: The weather, and therefore the climate, also affects how much energy can be produced from non-carbon-emitting sources.

This can mean something as simple as smoke produced by wildfire obscuring the sun and leading to less solar power production, but it really matters a lot for power derived from rain and snowmelt.

In the United States, a major portion of our non-carbon-emitting energy comes from hydropower. And hydropower capacity — literally the amount of water stored in reservoirs — is affected by the climate.

In the Pacific Northwest, which has an extensive system of dams that provide much of the region’s power, the Energy Information Administration expects that hydropower generation will fall off by about a fifth for 2023 compared to 2022 — 19 percent to be exact.

The EIA credited the forecast reduction to “above-normal temperatures in May ... [that] melted snow rapidly, resulting in a significant loss of water supply.” In the first six months of the year, hydropower generation fell off by 24 percent.

But what climate can take away in one region, it can give in another. While the Northwest has about half of the country’s hydropower, much of the remainder is in California, which experienced a record-setting wet and snowy winter. And that means very full reservoirs. The EIA said that the state had 94 percent more hydropower generation in the first half of the year compared to 2022 and expected almost double 2022’s generation for the whole year.

And that pattern may be repeated.

The expected El Niño weather pattern this winter “is associated with wetter-than-average conditions in the Southwest United States, including parts of California, and warmer-than-average temperatures in the Northwest,” according to the EIA.