Big Island drought

HILO — Point your index finger to the ground and measure to about the first two knuckles. That’s about 2 inches, the amount of water that a rain gauge at Waikoloa town has gathered this year.

The dry side of the island is famed for its clear weather, but the current and worsening drought is increasingly being manifested in dead trees and dust. The gauge at Waikoloa has recorded 1.94 inches of rain so far this year, and nothing significant since early July.

While East Hawaii has had below-normal rainfall, it’s nothing like the ongoing dry spell that has gripped the west side.

A rain gauge at Kona’s Keahole Airport has recorded just 3.46 inches, and nothing significant since mid-May.

The fire-singed lands around Pahala have recorded just 12 inches, but less than 2 inches since March.

East Hawaii gauges are below normal, but there is no drought situation because of regular trade wind weather. Glenwood, for example, has topped 88 inches for the year.

“2010 is, I think, for a lot of people, was worse, especially for the Ka‘u coffee farmers,” said Kevin Kodama, hydrologist for the National Weather Service’s Honolulu Forecast office. “I think one of the big issues is that we’ve been in drought since June of 2008.”

For a drought disaster, it’s hard to top what happened in 2010, when portions of Ka‘u endured months without rain; some places recorded lowest-ever rainfall totals.

While conditions have not reached D-4, or exceptional drought levels as measured by the U.S. Drought Monitor, a large swath of the South Kohala and North Kona coast is experiencing D-3, or extreme drought conditions. This is the second-strongest drought category.

Kodama’s monthly drought information statement shows how the dry season has gripped the island.

“Pastures and general vegetation over most of the South Kohala district were in very poor condition,” the statement said in May. “Reports indicated that there was little or no edible forage for livestock. Ranchers in these areas have already destocked cattle and water hauling operations have been ongoing for many months.”

“There is an increasing risk of significant brush fires in these areas,” the report said in June.

In July, “A South Kona farmer reported increasing irrigation costs for macadamia nut orchards as well as reduced yields from citrus and star fruit trees. … There is a very high risk of significant brush fires in these areas (Ka‘u and Kohala).

And on Aug. 9: “Ranchers operating near South Point reported that pastures have dried out and they have been supplementing feed. On the north side of the island, a rancher near Waimea reported insufficient forage for his cattle and he has been hauling 5,000 gallons of water each week. Pastures and general vegetation over most of the South Kohala district and portions of the North Kona district along the north-facing slopes of Hualalai have been very dry.”

What really hurts the farmers, Kodama said, is the persistence of the drought. If it were a one-time dry spell, the impact would not be as bad.

Although an El Niño event may have been the trigger for this latest dry spell, a couple of La Niña events have come and gone since 2008 without much relief. Kodama drew a parallel between the lengthy drought between 1998 and 2001.

In East Hawaii, the days of rain falling has been above normal, but the amount of precipitation is below normal. Forecasters are unsure how much of this is related to global climate change patterns.

But they are sure it can get worse.

The U.S. Climate Prediction Center, another arm of the National Weather Service, predicts a 40 to 45 percent chance of below-normal rainfall into early 2013, following the resumption of a weak to moderate El Niño.