IN response to the “confused” Robin O’Hara (Letters, June 20).

Beyond 3.1 miles the bottom of the turbine masts start to be screened by the earth’s curvature.

But all 121 Navitus turbines proposed are 656 feet tall above sea level. From 9.3 miles away on the beach you would see 656 feet minus 49 feet, so 607 feet would be visible above the horizon.

But from Bournemouth East Cliff, Durlston, or the Isle of Wight, the height of the viewpoints would overcome all the screening due to the earth’s curvature, such that the full 656 feet from base to blade tip will be visible from all around Poole Bay.

You need to grasp the scale and setting of the world’s largest offshore windfarm. The Needles lighthouse is 102 feet tall. The top of Tennyson Down on the IoW is 482 feet high. But, when viewed from Durlston Castle on the World Heritage Site, the windfarm would appear 1.8 times wider and 2.8 times higher than the Isle of Wight, a confused mass of industrial blades dominating the natural view.

Which is why UNESCO warned of the threat to the WHS status if Navitus goes ahead.

KATE SALWAY

Irving Road, Bournemouth