BAROUK CEDAR FOREST, Lebanon — Walking among the cedars on a mountain slope in Lebanon feels like visiting the territory of primeval beings. Some of the oldest trees have been here for more than 1,000 years, spreading their uniquely horizontal branches like outstretched arms and sending their roots deep into the craggy limestone. They flourish on the moisture and cool temperatures that make this ecosystem unusual in the Middle East, with mountaintops that snare the clouds floating in from the Mediterranean Sea and that gleam with winter snow.
But now, after centuries of human depredation, the cedars of Lebanon face perhaps their most dangerous threat: Climate change could wipe out most of the country’s remaining cedar forests by the end of the century.
As temperatures rise, the cedars’ ecological comfort zone is moving up the mountains to higher altitudes, chasing the cold winters they need to reproduce. But here in the Barouk forest, part of the Shouf Biosphere Reserve, south of Beirut, there isn’t much farther up to go. If the climate warms at the rates expected because of the continued rise of greenhouse gas emissions in the atmosphere, some scholars say that by 2100 cedars will be able to thrive only at the northern tip of the country, where the mountains are higher.
In the north, though, there are different problems. Lebanon’s densest cedar forest, the Tannourine Cedars Forest Nature Reserve, has lost more than 7 percent of its trees to insect infestations unknown before 1997. They are directly tied to a warming, drying climate.
Throughout history, the cedars of Lebanon have been prized for buildings and boats, chopped down for temples in ancient Egypt, Jerusalem, and beyond. So while climate change did not start the assault on the cedars, it could be the death blow.
Many thousands of square kilometers of forest once spread across most of Lebanon’s highlands. Only 17 square kilometers of cedars remain, in scattered groves.
The country’s most famous cedar patch, sometimes called Cedars of God, has been fenced off for preservation since 1876.
UNESCO added Cedars of God to its list of world heritage sites 20 years ago. The forest is isolated, and its ability to expand is limited. Now UNESCO says it is one of the sites most vulnerable to climate change.
Some believe that patch was where the resurrected Jesus revealed himself to his followers, said Antoine Jibrael Tawk, an author of books on the cedars.
The Lebanon cedar, a distinct species known scientifically as Cedrus libani, grows mainly here and in Turkey. The trees germinate in late winter because they need a freeze, preferably with snow.
This year, winter was mild. Omar Abu Ali, the ecotourism coordinator for the Shouf Biosphere Reserve, Lebanon’s largest protected area, pointed to evidence on the ground in the Barouk forest.
It was early April, and cedar seedlings were beginning to pop up from the soil. Normally the seedlings don’t come up until early May. Earlier, they risk dying in cold snaps and are more vulnerable to insects. “This is early germination,” Abu Ali said. “They can die.”
A generation ago, it typically rained or snowed 105 days a year in the mountains. High up, snow stayed on the ground for three to four months. This past winter, there were just 40 days of rain and a only month of snow cover.
“Climate change is a fact here,” said Nizar Hani, the Shouf Biosphere’s director. “There is less rain, higher temperatures, and more extreme temperatures,” both hot and cold, he said.
“The cedar forest is migrating to higher altitudes,” he said. And it is unclear, he added, which of the species that usually live alongside the cedars will survive higher up, further changing the ecosystem.
A 2010 study suggested that if the climate warms at expected rates, no more cedars will thrive in the Shouf, because the mountains there are not high enough. While some Lebanese specialists view that prediction as overly dire, they agree the cedars face an emergency.
“We are in a race,” said Hani. “There is no time to lose.”
Four years ago, Lebanon’s Agriculture Ministry began a new plan to plant 40 million trees, including some cedars. Separately, the Environment Ministry supervises the management of protected cedar areas. Yet even today, political divisions and the war’s legacy make the government too weak and fragmented to build functional national systems for electricity, water delivery, sewage or trash removal, let alone a muscular, enforceable master plan to protect the cedars, ecologists say.
Still, many Lebanese see in the tree a reflection of their land’s uniqueness and its ability to survive the storms of history.
“It is a very strong tree, strong enough to be able to live in very hard conditions,” said Hani, the Shouf Biosphere director. “It’s very unique, noble, different from any other kind of tree.”