Now scientists are suggesting a climatic explanation for this great upheaval: A long dry period caused droughts, hunger and mass migration. Such is the conclusion of a three-year study published this week in Tel Aviv: Journal of the Institute of Archaeology of Tel Aviv University.
The researchers drilled deep under the Kinneret, retrieving 18-meter strips of sediment from the bottom of the lake. From the sediment they extracted fossil pollen grains. “Pollen is the most enduring organic material in nature,” says palynologist Dafna Langgut, who did the sampling work.
According to Langgut, “Pollen was driven to the Kinneret by wind and streams, deposited in the lake and embedded in the underwater sediment. New sediment was added annually, creating anaerobic conditions that help preserve pollen particles. These particles tell us about the vegetation that grew near the lake and testify to the climatic conditions in the region.”
Radiocarbon dating of the pollen revealed a period of severe droughts between c. 1250 and 1100 B.C.E. A sediment strip from the Dead Sea’s western shore provided similar results.
Langgut published the study with Prof. Israel Finkelstein of Tel Aviv University, Prof. Thomas Litt of the University of Bonn and Prof. Mordechai Stein of Hebrew University’s Earth Sciences Institute.
“The advantage of our study, compared to pollen investigations at other locations in the Middle East, is our unprecedented frequency of sampling – for about every 40 years,” says Finkelstein.
“Pollen is usually sampled for every several hundreds of years; this is logical when you’re interested in prehistoric matters. Since we were interested in historical periods, we had to sample the pollen more frequently; otherwise a crisis such as the one at the end of the Bronze Age would have escaped our attention.” That crisis lasted 150 years.
The research shows a chronological correlation between the pollen results and other records of climate crisis. At the end of the Bronze Age – c. 1250-1100 B.C.E. – many eastern Mediterranean cities were destroyed by fire. Meanwhile, ancient Near Eastern documents testify to severe droughts and famine in the same period – from the Hittite capital in Anatolia in the north to Ugarit on the Syrian coast, Afek in Israel and Egypt in the south.
The scientists used a model proposed by Prof. Ronnie Ellenblum of Hebrew University, who studied documents that describe similar conditions of severe drought and famine in the 10th and 11th centuries C.E.
He showed that in areas such as modern Turkey and northern Iran, a reduction in precipitation was accompanied by devastating cold spells that destroyed crops.
Langgut, Finkelstein and Litt say a similar process occurred at the end of the Bronze Age; severe cold spells destroyed crops in the north of the ancient Near East and a reduction in precipitation damaged agricultural output in the eastern steppe parts of the region. This led to droughts and famine and motivated “large groups of people to start moving to the south in search of food,” says Egyptologist Shirly Ben-Dor Evian of Tel Aviv University.