At particular risk is the Gnarled Mossy Cloud Forest. This forest is a globally unique ecosystem as it is found only on the two peaks of Lord Howe Island, at altitudes of over 750m. This unique ecosystem is directly threatened by Climate Change as the average temperature rises and rainfall and cloud cover become more variable.

Temperatures have risen over the past century, and are expected to continue to increase in the future. Plants growing in the Cloud Forest on Mount Gower summit are particularly vulnerable to rising temperatures because they cannot move to a higher, cooler altitude to adjust to warming temperatures.

There has also been a decline in annual rainfall over the past 100 years on Lord Howe Island. Lord Howe experienced its lowest annual rainfall in 2018 (984.6 mm), according to data collected by the Bureau of Meteorology (BOM). 

Lord Howe also had its driest December on record in 2018, with just 8.2 mm of rainfall, and its driest January on record in 2019, with only 1 mm of rainfall during the month, less than 1% of what the island would usually see at that time of year. Three hot dry summers 2017, 2018, 2019 have impacted the Gnarled Mossy Cloud Forest through canopy trees and epiphytes dying. Rainfall variability is projected to increase in the future.

Since 1945, there has been a long-term decline in the proportion of days with cloud cover around the mountain peaks on Lord Howe Island. The semi-permanent cloud layer is important in sustaining the Gnarled Mossy Cloud Forest, as it provides the moisture and humidity needed to keep the unique plant communities alive. This is particularly vital during periods of low rainfall. 

Cloud loss also increases the direct solar radiation exposure which heats and dries out the canopy, threatening the existence of this unique forest. As air temperatures continue to rise with climate change, scientists anticipate this will increase the altitude at which clouds form over tropical mountains, adding further pressure to the ecosystem.