The Neolithic period in the Levant has puzzled researchers trying to resolve climatic vs. anthropogenic chain of events. The records reviewed here include counting of micro-charcoal particles in a sedimentary core from Lake Hula, Carbon and Strontium isotopes in speleothems. These are supplemented by sedimentary observations in various environments, which show a thick accumulations of reworked soils in various sedimentary traps, associated with Neolithic settlements and overlying late Pleistocene Lake Lisan deposits. Extreme peaks of micro-charcoal and speleothem carbon isotopes are explained by fires, causing removal of vegetation and soil. Increased lightening intensity was probably the main igniting cause. A pulse of low 87Sr/86Sr ratios and sedimentary sections indicate that soil was eroded from hillslopes and redeposited in sediment traps such as valleys. The low 87Sr/86Sr values correspond to the entire Neolithic period. An increase in lightning thunderstorms was associated with the orbital-forcing-controlled high solar radiation during the early Holocene, causing a short-term marginal penetration of southern climate systems into the southern Levant, culminating between ~ 8 and 8.6 ka. Low Dead Sea levels indicate that this period was dry, coeval with the 8.2 ka cold and dry event of the northern hemisphere, possibly amplifying the catastrophic effects.
The various records infer that the environmental catastrophes resulted from a climatic shift, rather than an anthropogenic cause, such as intentional burning. Increased lightening intensity probably promoted an intensive fire regime which caused major loss of vegetation and soil degradation.
During the Neolithic period, the redeposited soils provided favorable conditions for early agriculture and coincided with the concentration of large Neolithic settlements in the Jordan Valley, while contemporaneous abandonment occurred in upland areas. The extreme fire regimes could promote the technological innovations of pottery production. The fact that pottery development coincided with the peak of environmental stress is significant.