Why La Nina weather pattern may be good news for Europe this winter

A pedestrian in Chicago earlier this year. La Nina means winter is likely to bring drier than average conditions across US southern states. AP

The famous frigid British winter of 1946-1947, coming just after an earlier European war, brought coal shortages, electricity blackouts, frozen crops and farm animals, and more rationing. When the snow melted in March, floods brought further misery. The pound was devalued, and the Labour Party lost 78 seats in the next election. Today, Europe’s economy, energy security and even foreign policy again hinges on the weather.

It has been a tough couple of years for energy systems against weather. Early last year, Texas was struck by a freak ice-storm which froze gas, coal and nuclear power stations and wind turbines. California has suffered a string of blackouts as forest fires damage power lines or force their shutdown as a precaution.

A drought last year cut South America’s hydropower, forcing it to import more liquefied natural gas (LNG). Northern Europe experienced one of the least windy years in the last four decades, limiting wind power output. Together these events set the stage for Russia to tighten the European gas market ahead of this year’s shortages and huge run-up in prices.

An intense heatwave hit India and Pakistan in April to May this year. Shortages of power generation and coal led to India’s worst electricity shortages for six years. Then last month’s massive floods in Pakistan damaged gas pipelines, electricity cables and dams, worsening an existing power crisis.

This summer, droughts and heatwaves across the western US, Europe, Iran and China saw air-conditioning requirements soar, just as output from hydroelectric dams and nuclear plants — which need water for cooling — slumped. Norway’s hydropower is a critical balancing factor for neighbouring countries, but its reservoirs reached their lowest levels for a quarter-century and Oslo had to consider limiting exports. Low water in the Rhine and other major rivers interrupted transport of coal and oil by barge.

With the concentration of LNG export plants and oil refineries along the Gulf of Mexico coast, the US is lucky this hurricane season has been quiet. The worst ones, notably last month’s Hurricane Ian, battered the Caribbean and Florida rather than energy infrastructure.

Two phenomena link many of these weather disasters: the long-term backdrop of climate change, meaning a rapidly-heating planet with extreme summer temperatures; and La Nina. This meteorological pattern brings cool water to the surface of the eastern equatorial Pacific Ocean. It is the converse of El Nino, which alternates with it on a two to seven-year cycle, interspersed with neutral periods.

La Nina is linked to drought in the western US, Brazil and Argentina, east Africa and eastern China, but wet conditions across south-east Asia and the eastern US. This is the third La Nina year in a row, rare though not unprecedented.

With Russian gas supplies all but cut off, Europe needs a mild winter to avoid burning through its fuel storage. Roughly 40 per cent of European gas demand is in buildings — mostly, heating — and 30 per cent for electricity generation.

The EU’s Copernicus service forecasts this winter in Europe will be warmer than usual, but that there could be a cold spell in December. La Nina may be good news for Europe overall: it tends to bring warm, wet westerly winter winds, boosting renewable output and refilling parched reservoirs and rivers. Last winter was rather mild, crucially for avoiding a worse gas crisis just before the outbreak of war.

But La Nina can also increase the likelihood of a breakdown of the polar vortex, allowing chilly Arctic air to rush southwards. A blocked high-pressure zone over north-west Europe would bring clear skies with little wind and freezing temperatures — the worst combination for the energy system.

Meanwhile, the US east coast is also expected to be warmer than usual. That moves the focus to the globe’s third key area of winter fuel demand: north-east Asia, a big importer of LNG and oil. China has been reselling LNG surplus cargoes to Europe, as Covid lockdowns have reduced demand, but last week the government told its gas companies to stop exports to ensure sufficient domestic supplies.

Here, the European Centre for Medium-Range Weather Forecasts suggests November-December temperatures will be about average, and January and February above average.

These weather factors remain highly uncertain: other forecasters see a slightly colder winter than average. We should have a clearer picture for this winter in November when key wind patterns become established.

Europe has refilled most of its gas storage ahead of schedule. Gas prices have dropped sharply from stratospheric records and are only a little above last year’s levels. But a cold winter would see stocks depleted by March or April. If icy conditions do arrive in December, it will take nerve from policymakers and gas companies to hold on in the reasonable expectation of a warmer start to next year.

Then with inventories depleted and Russian gas largely unavailable for a full year, the continent will face the challenging task of again refilling storage before November 2023. That will in turn depend critically on the levels of wind and water, and whether a repeat of the heatwave pushes up electricity needs and dents nuclear output. An eventual switch into El Nino conditions may bring colder winter weather to northern Europe, although the phenomenon’s exact impact on the continent is unclear.

Every new data point and weather forecast will swing gas and electricity prices. Even a milder cold snap than 1947 could be disastrous with the icicle-thin margins Europe has to cope with. The eastern Pacific may be a long way off, but the North Atlantic alliance will be watching it intently.

Robin M Mills is CEO of Qamar Energy, and author of The Myth of the Oil Crisis