Why Japan's wasabi farmers fear climate change

STORY: 70-year-old Japanese farmer, Masahiro Hoshina, has been growing wasabi in Okutama, west of downtown Tokyo, for years.

But as typhoon season approaches, he’s getting concerned about his future.

It took farmers years to recover from Typhoon Hagibis which hit Japan in 2019.

It swept away crops and slashed production by 70%, according to local data.

"Recently, the power of a typhoon feels totally different from before due to global warming. It’s getting stronger. The wind is stronger and it rains a lot when a typhoon arrives."

Hoshina is bracing himself once again.

And the restaurants at the other end of the chain are worried they'll have to go without.

Experts say global warming is posing a real threat to the production of wasabi.

And it’s not only the typhoons.

Rising temperatures are also threatening the growth of the plants which need to be in water at a consistent 50-60 degrees Fahrenheit year-round.

Kyoko Yamane is an associate professor of applied Biological Sciences at Gifu University.

"Global warming is considered to be one of many factors affecting wasabi production. When the water temperature rises, the amount of oxygen decreases which affects the growth of wasabi. The decreasing snow cover indirectly results in animals creating more damage to wasabi fields, which also discourages farmers. In addition to this, damage from flooding becomes more frequent and that hits farmers as well."

Restaurants, like this one in the capital Tokyo, are already feeling the pinch of supply shortages.

Noodle restaurant Sojibo fears it may not be able to serve fresh wasabi in the future, and has already changed its menu to make it only available with certain dishes, says head sales manager, Norihito Onishi.

"We would like to provide raw wasabi to customers the same way as before. But if this unstable supply of wasabi persists due to many factors including global warming, we will face a situation where we need to come up with other ways to overcome the problem so that we don’t end up not serving raw wasabi at all."

It's not just the weather that's impacting wasabi farmers.

A drop in rural populations due to ageing means there are also fewer successors.

The two factors have meant that the output of wasabi grown in clear-flowing water, like at Hoshina's farm, has fallen to half that of 2005, according to the Agriculture Ministry.