Scientists are in agreement that in order to mitigate climate change, we must reduce emissions, plant more forests, and increase renewable energy usage. However, there may be situations where these approaches compete against each other.
A recent study from the Weizmann Institute of Science focuses on an important aspect of this debate: the effectiveness of solar power versus tree planting in combating climate change. The study was published in PNAS Nexus.
The study primarily explores the concept of “break-even time” (BET). BET refers to the duration needed for a climate change mitigation strategy to start producing a net positive impact.
Surprisingly, the research reveals that in arid regions, solar farms have a far shorter BET compared to tree planting. Solar farms have a BET of approximately 2.5 years, whereas tree planting has a BET of over 50 years. In other words, solar farms are about 20 times more effective as a climate solution than tree planting.
This finding is pivotal, as arid regions have the most land available for both tree planting and solar farms.
After analyzing arid climates, the researchers went on to study humid climates. The researchers found that tree planting becomes a more effective climate strategy in humid areas. However, humid areas generally have little land available for tree planting.
On the other hand, solar farms maintain their quick BET regardless of location. This highlights their versatility as a tool for mitigating climate change.
Tree planting as a climate strategy has other limitations. Mass tree planting tends to replace diverse ecosystems with monocultures. This can put native species at risk, and it makes forests far more susceptible to disease.
Although planting trees is a less effective climate strategy than building solar farms, forests do offer a wide range of benefits. These include soil protection, air purification, and recreation opportunities. These aspects should be taken into account when considering an environmental policy approach.
As ZME Science notes, policymakers would ideally integrate both approaches. They should start with building solar farms and then incorporate sustainable forest management in parallel.
Image Source: Elvis Mugari
