Heat wave threats on the rise in scorched US

In west, hazards range from strains on grid to toll on wildlife and crops

A record-shattering heat wave rolling across the Western US is threatening the region's power grid, as well as taking a toll on endangered wildlife and agricultural products.

Most of the states of Washington, Oregon, Idaho and parts of Nevada, California and Montana were placed under an excessive heat warning on Tuesday afternoon, part of a "historic and dangerous heat wave" gripping the western part of the United States, the National Weather Service said.

The agency predicted scorching temperatures of 43.3 C to 48.9 C across Washington, Oregon, and northern and central Idaho this week after heat records tumbled across the vast region at the weekend.

"Seek air conditioning if possible. Stay hydrated and take frequent breaks," the weather service warned in a message on its website.

The heat wave comes amid a mega-drought that has dried up vegetables amid the sweltering temperatures in the western states.

More than 58.4 million people live in an area affected by drought, encompassing California, Nevada, Arizona, Utah, New Mexico, Oregon, Washington, Idaho and Montana, according to the US Drought Monitor, which tracks climate patterns.

The agency said 49.7 percent of the Western US is in extreme and exceptional drought. The last time the region was embroiled in a dry spell of this scale was July 2002, when the corresponding figure was 45.3 percent.

"Wildfires and increasing wildfire danger, water restrictions, and damage to agriculture are very common across the west region," the US Drought Monitor, said in a recent update.

US President Joe Biden linked the extreme heat to climate change.

"And as climate change induces extreme weather events more and more frequently, we need to make investments to build a more resilient grid to carry this electricity," Biden said during a speech on Tuesday in La Crosse, Wisconsin, to sell a bipartisan infrastructure bill.

Power system

A consequence of the heat is the strain it imposes on the electricity grid system. Last year, hundreds of thousands of Californians experienced rolling energy blackouts during the height of the summer as the state temporarily shut off power.

The California Independent System Operator, the state's electric grid operator, said on Sunday that it was poised to issue a Flex Alert-a call for people to voluntarily reduce power usage-in anticipation of increased electricity demand.

California employs renewable sources such as solar energy and hydro plants to produce electricity. But the unprecedented heat wave, combined with the deepening drought, has dried up reservoirs.

The water level in Northern California's Lake Oroville, a key reservoir for the state, has fallen so low that state officials predict they will be forced to close the power plant for the first time since it opened in 1967.

The depletion of stream flows across lakes and rivers in the state threatens the survival of native fish, such as California's endangered salmon population.

The California Department of Fish and Wildlife is trucking millions of Chinook salmons from Central Valley downstream to the Pacific Ocean due to rising temperatures in the region's river that might kill the baby salmon.

The reduced water supply also means farmers will have less water to irrigate their lands.

The US Bureau of Reclamation, which oversees water resource management, announced in May that it will reduce water deliveries to many farm contractors in Central Valley, a move which would force farmers to cut back on crop production.

Agriculture makes up a significant portion of California's economy, which produces over a third of the country's vegetables and two-thirds of its fruits and nuts.

Due to the unrelenting drought and dwindling water supply, many farmers in the state have resorted to idling land and replacing plants that consume a lot of water, such as almonds, in favor of less water-intensive ones.