This chapter presents a selection of examples that illustrate how lake records have advanced our understanding of patterns and controls of Holocene climate. A hierarchy of temporal scales of climate variation influence lake behaviour: From orbital cycles, to millennial and centennial changes in sea-surface temperatures or solar radiation, to multi-annual variation in the linked ocean-atmosphere system associated with synoptic climate features, such as the El Ni-o Southern Oscillation or the North Atlantic Oscillation. Orbital forcing affects not only temperature of continental areas but also atmospheric circulation systems that drive winds and precipitation. Thus, there is considerable spatial variation in Holocene moisture patterns at orbital scales related to the positioning and strength of surface pressure systems that drive the penetration of moisture from the oceans onto the continents. In North America, the Laurentide ice sheet, which persisted until the Mid-Holocene, also had major impacts on circulation patterns and hence on moisture and temperature gradients in the Early and Mid-Holocene. In many cases, higher frequency oscillations are superimposed upon an overall envelope of change at orbital time-scales. Millennial-scale cooling events in the North Atlantic region, as well as solar variation at multiple temporal scales, appear to drive drought cycles, as evidenced in paleolimnological records throughout the Americas, Europe and Africa. How insolation forcing interacts with other modes of climate variation operating at millennial- to sub-annual-scales is not understood and will require long sequences of high-resolution data that span the entire Holocene.
|Original language||English (US)|
|Title of host publication||Global Change in the Holocene|
|Publisher||Taylor and Francis|
|Number of pages||15|
|State||Published - Jan 1 2014|
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)