As Hawaii works to reduce its electrical energy load the emphasis has been on new energy saving technology. The discussion is of more solar panels, batteries and hydrogen. Maybe there is another solution that is equally important: planting more  trees. Because Hawaii is steadily losing tree cover.

There are a number reasons for this; an emphasis on the need for new homes to accommodate solar panels. In practice, in some new housing developments on Oahu, trees are deliberately not planted lest they create shade that would reduce their ability to generate electricity. In addition, the practice of building ‘monster homes’ that take up and entire residential lot, and ohana zoning add-ons to existing homes – long established trees are being cut down and removed from older residential neighborhoods. The estimated loss of trees is 5% or approximately 76,000 trees over 4 years. This is affecting our quality of life not just because it affects the beauty of our city but because it increases Honolulu temperatures.

There are a number of reasons for this. As a result of the loss of trees and on going construction on Oahu, our city is getting hotter.  This  is a result of a number of factors. More than a million tons of oil based asphalt is laid per year.  In addition, the construction of the Honolulu rail project and the building of more homes  the creation of concrete islands in the middle of streets to slow down speeders, the amount of concrete and asphalt paving has increased substantially. The concrete and asphalt holds heat – creating heat islands.

This is what the State Division of Forestry and Wildlife wrote in its assessment of Honolulu;https://smarttreespacific.net/wp-content/uploads/Tree-Canopy-Report-Honolulu-2016_revised091117.pdf

“Honolulu is losing tree canopy; in fact, we lost nearly 5% of our total urban tree canopy over four years. The majority of losses were in non-public zoning areas. Net Residential losses alone totaled 355 acres representing 39% of all the tree canopy loss; some land use parcels near Kalaeloa Airport saw unprecedented clear cutting resulting in 100% canopy loss. All land use areas saw decreases; even our conservation areas saw a 1% loss in tree canopy.  Close to 98% of the losses were less than a quarter acre each and spread widely across the landscape. These losses equate to at least 76,600 trees. New plantings did occur totaling about 230 acres, which is far short of what is needed to keep pace with the losses, especially considering the time required to grow a canopy.”

Maybe before we begin thinking of more dramatic technical solutions to our problems of increasing temperatures in Hawaii, we should take action to restore our tree cover.