  Targeted ultra-high resolution Laser Ablation Inductively Coupled Plasma Mass
Spectrometry (LA-ICP-MS) analysis of an ice core drilled in the Pamir Mountains
of Central Asia (CA) records changes in seasonal patterns of atmospheric
circulation and moisture delivery to CA over the past 1600 years. Fe, Ca, and
Mg signals in the LNC3 Pamir ice core reflect variable delivery of these
elements during the pre-Medieval Warm Period (pre-MWP), Medieval Warm Period
(MWP), and during the onset of the Little Ice Age (LIA) in CA. During the
pre-MWP, hiatuses between dust seasons are observed due to a lengthened
accumulation season, and dust delivery limited to a short period at the end of
the accumulation season when modern summer-style northerly airflow occurred.
During the MWP, dust delivery to CA decreased, though Fe-intensity in the core
indicates episodic northerly air incursion. By the onset of the LIA, dust
availability increased due to regional drying and strengthening winds, and
strong westerlies blocked meridional flow reducing Fe-rich dust input from the
north. CA has experienced recent warming, desiccation, weakening winds, and
glacier loss. Major climate circulation drivers (Westerlies, Icelandic Low,
Siberian High) continue to display LIA-style patterns, and annual temperatures
are approaching those of the MWP. While none of the preceding climate periods
in CA history can serve as an absolute wholesale proxy for conditions that are
likely to prevail in the near future continued Northern Hemisphere westerlies
weakening in a changing climate may enhance meridional flow and bring more
moisture into the Aral Sea catchment from the Arctic.
