North American Tree Rings, Climatic Extremes, and Social Disasters - Dendroclimatology - page 312

2006 ) illustrating the apparent sensitivity of the seventeenth-century economy in
New Mexico to severe drought. Indeed, the hardship associated with this dry spell
may have helped trigger the Pueblo Revolt of 1680, which drove the Spaniards out
of New Mexico for more than a decade. This seventeenth-century 'Pueblo' drought,
named for the region where the socioeconomic impacts have been documented in
greatest detail, may serve as a useful model for the environmental and agricultural
impacts of protracted drought among prehispanic Puebloan societies. These impacts
may include the controversial effects of the Great Drought on the Anasazi soci-
eties of the Colorado Plateau, although the Anasazi did not suffer Apache raids or
Spanish colonization in the late thirteenth century. The seventeenth-century Pueblo
drought also offers a vivid spatial contrast to the geographical distribution of the
early twentieth-century pluvial (Fig. 10.3 ) , but it reproduces reasonably well the
intensity, duration, and spatial impact of the recent drought over the Southwest that
began in 1999 (Drought Monitor 2004 ) .
Bald cypress tree-ring data from the Tidewater region of Virginia provide an
interesting perspective on the human impact of drought extremes during the early
English settlement of North America. Jamestown was founded in April 1607, the
second year of a 7-year regional drought more severe and long-lasting than any
other such event in more than 700 years (Stahle et al. 1998 ) . The tree-ring data
were calibrated with the Palmer Hydrological Drought Index (PHDI; Stahle et al.
1998 ) and, along with archival information on mortality among the colonists, pro-
vide statistical evidence for the sensitivity of this early English colony to drought.
Mortality and the reconstructed PHDI for the Tidewater region of Virginia and North
Carolina are significantly correlated for the first 18 years of English occupation,
with most deaths arising from starvation and disease in drought years (Fig. 10.11 ;
r 0.001, for 1608-1624 at Jamestown and including 1586, the one

year with mortality data from the Roanoke Colony [Stahle et al. 1998 ] ). In fact, just
38 of the initial 104 colonists survived the first year at Jamestown, and only 1200
out of the 6000 settlers sent to Jamestown in the first 18 years of settlement were
still living by 1624.
The drought sensitivity of the early English settlers at Jamestown seems to have
been heightened by their dependence on the trade and tribute of food supplies from
the native Algonquin. The Spanish sphere of influence in North America during
the sixteenth century extended from Mexico and Florida northward up the Atlantic
coastline into the Chesapeake Bay, and it included missionary settlements in modern
South Carolina (Paar 1999 ) and Virginia (Lewis and Loomis 1953 ) . Father Juan
Bautista de Segura at the Chesapeake Bay and authorities at the Santa Elena colony
in South Carolina both referred to extended drought, parched soil, food shortages,
famine, and death in the 1560s (Lewis and Loomis 1953 ; Anderson et al. 1995 ) .
These accounts refer to the hardships and food shortages suffered by the native
people during drought well before the settlement of Jamestown, but this drought
sensitivity would presumably have been shared by Spanish or English colonists who
depended on the natives for their food supply.
The drought sensitivity of the early English settlers at Jamestown also arose
from the specific location of the colony on the lower James River estuary near the

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