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work is underway to improve and refine modelling approaches. Palaeo-records of fire, cli-
mate, and vegetation can be used to test whether models can accurately simulate past fire
and climate regimes through hind-casting, thereby improving confidence in our ability to
predict and manage future changes in fire regimes (Gavin et al. 2007). Data-model compari-
sons advance our understanding of fire regimes, fire-vegetation feedbacks, and the role of
humans in influencing fire (Scholze et al. 2006, Power et al. 2010, Kehrwald et al. 2013).
The boreal forests of North America have experienced varying fire return intervals over the
Holocene and have become a focus for palaeo-modelling comparisons (Bergeron et al. 2011,
Carcaillet et al. 2011, Girardin et al. 2011). For example, Flannigan et al. (2001, 2005) simulated
fire danger in Canada's boreal forest for the warmer climate of 6000 bp and found generally
good agreement with charcoal records. Discrepancies between the 6000 bp charcoal data
and simulated fire danger in the lee of the western cordilleras highlighted the impact of oro-
graphic effects on rainfall, providing opportunities for improving simulations using climate
models with higher spatial resolution. Under forecasted 2100 ce climate conditions, fire dan-
ger is predicted to increase in much of western Canada, but not in the east, due to predicted
increases in humidity (Flannigan et  al. 2005, Hely et  al. 2010). Despite these interactions
between fire and climate, boreal forests have shown little change in vegetation, suggesting
resilience to Holocene climate and fire return intervals over the range of variability of the past
c. 11,000 years (Bergeron et al. 2011, Carcaillet et al. 2011). However, Hely et al. (2010) suggest
that predicted warming caused by anthropogenic greenhouse gases, if not accompanied by
increased rainfall, will increase fire risk in the eastern boreal forest towards the maximum of
its known historical range, which occurred in the warmer climate of the mid-Holocene. Fur-
thermore, it has been shown that stands of less than 100 years old have much shorter fire
return intervals than old-growth stands, and that as the percentage of old-growth forest has
been dramatically reduced, it seems that the effects of logging will push the future fire return
interval outside of the Holocene range (Cyr et al. 2009, Bergeron et al. 2011).
Alongside the advances in DGVMs, large collaborative projects and open access databases
are opening up opportunities for using palaeo data to validate model outputs by hindcasting
vegetation-climate interactions that are known from palaeo-records. For example, the Global
Charcoal Database provides free access to late quaternary charcoal records and provides excit-
ing opportunities for reconstructing fire history, and testing hypotheses regarding climate, fire,
and vegetation interactions (<http://www.gpwg.org/gpwgdb.html>). Such databases have
enormous potential for the integration of palaeoecological data into cross-disciplinary studies
of fire ecology and management (Power et al. 2010). Members of the Global Palaeofire Working
Group (GPWG) are currently exploring the impact of mid-Holocene fire, driven by coupled
ocean-atmosphere general circulation models from the Palaeoclimate Modelling Intercom-
parison Project (PMIP2) (<http://gpwg.org/>). PalEON (the PaleoEcological Observatory Net-
work) is an interdisciplinary team of palaeoecologists, ecological statisticians, and ecosystem
modellers. Using palaeoecological proxies, their aim is use palaeoecological reconstructions of
forest composition, fire regime, and climate in northeastern US and Alaska over the past 2,000
years, to drive and validate terrestrial ecosystem models. By simulating past climate-
vegetation-fire dynamics correctly, it should then be possible to understand and predict future
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