Climate Change on Rapa Nui

cc-1 — Aerial view of the Rano Raraku Wetland, dry since 2017.

Easter Island, also known as Rapa Nui, is an island territory of Chile located in the South Pacific Ocean, 3,700 kilometers from the mainland. The island is renowned for its iconic moai and rich Rapa Nui culture. However, it is facing a growing threat: climate change, one of the biggest impacts of which is on the native flora.

Extreme vulnerability

Easter Island's unique characteristics make it particularly susceptible to the effects of climate change:

Extreme isolation: Located thousands of kilometers from the mainland, the island is isolated from external influences, which limits its ability to adapt to environmental changes. A concrete example of this situation is the difficulty in importing resources or receiving specialized technical assistance to meet the challenges of climate change.
Small size: With an area of only 166 square kilometers, the island has a fragile and limited ecosystem, with less buffering capacity against external disturbances. An example of this is the rapid spread of forest fires or the rapid salinization of freshwater due to saltwater intrusion.
History of degradation: The island has experienced significant biodiversity loss and soil degradation in the past, which reduces its resilience to new challenges. A historical example of this situation is the massive deforestation that occurred on the island during prehistoric times, which has had a lasting impact on soil fertility and coastal erosion.
Current conditions: Easter Island's current climate is characterized by high aridity, high winds and low freshwater availability. These pre-existing conditions exacerbate the effects of climate change, making the island more vulnerable to drought, wind erosion and saline intrusion.

Rapa Nui is not the typical tropical island of Polynesia, rainy and with thick jungles. Rather, it is an island of low hills, stony grasslands, whipped by constant winds, very vulnerable to climatic factors.

cc3-1 — The widespread erosion on the island may be greatly exacerbated by climate change, especially drought followed by heavy rains and changes in wind patterns.

The following paragraphs will present a number of examples of the ways in which climate change is manifesting itself on Rapa Nui.

The climate crisis is manifested in various ways on Easter Island.

Sea level rise: Sea level rise does not represent in the case of the island such a direct threat, although it does add to the other degrading factors that contribute for example to erosion. The main threat is to coastal archaeological heritage, including moai and ceremonial sites. A concrete example of this risk is the gradual erosion of the base of the moai, which could lead to their eventual collapse.

Intensification of extreme weather events: More intense heat waves, prolonged droughts and lower winter temperatures are recorded, negatively impacting agriculture, native flora and fauna. An example of this is the increasingly frequent and severe droughts, and also the increase in cold winds, which are one of the most stressful factors for native plants.

Changes in precipitation patterns: The alteration of precipitation patterns has resulted in a reduction in the availability of freshwater, a vital resource for the island. This is exemplified by the decline in precipitation during the dry season, which impedes aquifer recharge and intensifies water stress on the island.

Impacts on natural resources and native flora on the island

Climate change has a profound impact on Easter Island's natural resources:

Soil erosion and degradation: Soil erosion and degradation: Increased wind intensity and water scarcity have accelerated soil erosion, reducing soil fertility and water retention capacity. A visible example of this problem is the formation of gullies and the loss of the little fertile soil in the areas most exposed to the wind.

Loss of biodiversity: Drought, rising temperatures and ocean acidification have caused the loss of native species of flora and fauna, which negatively affects the ecological balance of the island. The extinction of species with serious conservation problems and that have not been able to adapt to the new climatic conditions is a prospect that today seems very close.

Severe deterioration of wetlands: One of the most direct impacts of climate change on native flora is on wetlands, which have reduced their water bodies and in at least one case (Rano Raraku Wetland) have already been completely lost. The wetlands were the main reservoirs of germplasm in the wild, but today they conserve fewer species and smaller populations, seriously threatened by other factors, especially fires and uncontrolled cattle ranching.