Yatir Forest — Long-Term Semi-Arid Afforestation Carbon Sink (Israel)

The KKL-JNF (Jewish National Fund) began planting Aleppo pine at Yatir Forest in 1964, creating what would become Israel's largest afforested area — now roughly 3,000 hectares (30 km²) — in a semi-arid transition zone between Mediterranean climate and the Negev desert, on the plateau between Meitar and Arad, where annual rainfall is only about 280–300 mm.

An eddy-covariance flux tower installed around 1999–2000 by Prof. Dan Yakir's lab at the Weizmann Institute of Science, part of the global FLUXNET network, has continuously measured the forest's carbon fluxes for over two decades. Rotenberg et al. (2021) report net carbon accumulation of 145 ± 26 g C/m²/yr over 2001–2016 (roughly 1.45 tC/ha/yr), with about 71% stored in soil rather than biomass; an earlier Grunzweig et al. (2003, Global Change Biology) study found net ecosystem productivity of about 240 g C/m²/yr, comparable to forests in much wetter climates.

A key study by Rotenberg & Yakir (2010, Science) adds an important caveat: converting bright semi-arid shrubland to a darker forest canopy increases solar radiation absorption (reduced albedo) and reduces evaporative cooling — an effect roughly double the albedo effect alone — meaning it can take decades, or over a century, of carbon accumulation before the forest achieves net climate cooling.

National Geographic and Yale E360 reporting document drought-related tree mortality (the 2008–2009 drought brought 349 consecutive rainless days; 5–10% mortality over the past decade, up to 80% in some patches), limited natural regeneration due to grazing and drought, and ecologists' concerns that the pine monoculture displaces native open-landscape species.

Read the full analysis: https://www.science.org/doi/10.1126/science.1179998

Read the full analysis: https://www.science.org/doi/10.1126/science.1179998