@article {corvec_changes_2017,
	title = {Changes to the tropical circulation in the mid-Pliocene and their implications for future climate},
	journal = {Climate of the Past},
	volume = {13},
	year = {2017},
	pages = {135{\textendash}147},
	issn = {1814-9332},
	doi = {10.5194/cp-13-135-2017},
	url = {http://www.clim-past.net/13/135/2017/},
	author = {Corvec, Shawn and Fletcher, Christopher G.}
}
@article {minokhin_forecasting_2017,
	title = {Forecasting northern polar stratospheric variability with competing statistical learning models},
	journal = {Quarterly Journal of the Royal Meteorological Society},
	year = {2017},
	pages = {n/a{\textendash}n/a},
	abstract = {The northern polar stratosphere plays an important role in modulating wintertime near-surface temperatures in midlatitudes. Forecasting northern polar stratospheric variability therefore has the potential to extend the skill of seasonal winter weather forecasts. This research explores the utility of state-of-the-art statistical learning models for medium-range (10-20 day lead time) forecasting of northern polar stratospheric variability. In addition to indices representing the El Ni{\~n}o Southern Oscillation, the Quasi-Biennial Oscillation, and the 11-year solar cycle, indices of the upward flux of wave activity from the troposphere into the stratosphere (WAF) are used as predictors for modelling and forecasting stratospheric temperature and geopotential height anomalies. The WAF is known to provide the primary source of intraseasonal variability in the wintertime stratospheric polar vortex. Multiple linear regression, random forest, artificial neural network, and support vector regression (SVR) models were trained over the 1980-2005 time period, and replicated real-time forecasts were generated for the 2005-2011 time period. The highest correlation skill for 10-day forecasts (ρ =0.41 for temperature, and ρ =0.49 for geopotential height) was found using the SVR model, which represents an improvement in skill over previous work that did not include WAF, or lagged predictors. Using a permutation-based method the importance of each predictor was ranked, and the WAF predictors were found to be most important for improving forecast skill in all models. In addition to improved forecast skill, it is argued that the methods presented here represent an advance due to their increased simplicity and relative ease of physical interpretation.},
	issn = {1477-870X},
	doi = {10.1002/qj.3043},
	url = {http://onlinelibrary.wiley.com/doi/10.1002/qj.3043/abstract},
	author = {Minokhin, Ivan and Fletcher, Christopher G. and Brenning, Alexander}
}
@article {thackeray_quantifying_2016,
	title = {Quantifying the Uncertainty in Historical and Future Simulations of Northern Hemisphere Spring Snow Cover},
	journal = {Journal of Climate},
	volume = {29},
	year = {2016},
	pages = {8647{\textendash}8663},
	issn = {0894-8755, 1520-0442},
	doi = {10.1175/JCLI-D-16-0341.1},
	url = {http://journals.ametsoc.org/doi/10.1175/JCLI-D-16-0341.1},
	author = {Thackeray, Chad W. and Fletcher, Christopher G. and Mudryk, Lawrence R. and Derksen, Chris}
}
@article {thackeray_snow_2016,
	title = {Snow albedo feedback Current knowledge, importance, outstanding issues and future directions},
	journal = {Progress in Physical Geography},
	volume = {40},
	year = {2016},
	pages = {392{\textendash}408},
	abstract = {Over the past decade, substantial progress has been made in improving our understanding of surface albedo feedbacks, where changes in surface albedo from warming (cooling) can cause increases (decreases) in absorbed solar radiation, amplifying the initial warming (cooling). The goal of this review is to synthesize and assess recent research into the feedback caused by changing continental snow cover, or snow albedo feedback (SAF). Four main topics are evaluated: (i) the importance of SAF to the global energy budget, (ii) estimates of SAF from various data sources, (iii) factors influencing the spread in SAF, and (iv) outstanding issues related to our understanding of the physical processes that control SAF (and their uncertainties). SAF is found to exert a small influence on a global scale, with amplitude of \~{} 0.1 Wm-2 K-1, roughly 7\% of the strength of water vapor feedback. However, SAF is an important driver of regional climate change over Northern Hemisphere (NH) extratropical land, where observation-based estimates show a peak feedback of around 1\% decrease in surface albedo per degree of warming during spring. Viewed collectively, the current generation of climate models represent this process accurately, but several models still use outdated parameterizations of snow and surface albedo that contribute to biases that impact the simulation of SAF. This discussion serves to synthesize and evaluate previously published literature, while highlighting promising directions being taken at the forefront of research such as high resolution modeling and the use of large ensembles.},
	issn = {0309-1333, 1477-0296},
	doi = {10.1177/0309133315620999},
	url = {http://ppg.sagepub.com/content/40/3/392},
	author = {Thackeray, Chad W. and Fletcher, Christopher G.}
}
@article {fletcher_dynamical_2015,
	title = {The Dynamical Influence of Separate Teleconnections from the Pacific and Indian Oceans on the Northern Annular Mode},
	journal = {Journal of Climate},
	volume = {28},
	year = {2015},
	pages = {7985{\textendash}8002},
	abstract = {The northern annular mode (NAM) influences wintertime climate variability in the Northern Hemisphere, and understanding the processes controlling its sign and amplitude is of critical importance. Mounting evidence supports a robust teleconnection between the El Ni{\~n}o{\textendash}Southern Oscillation (ENSO) and the NAM, while internal variability generated in the tropical Indian Ocean (TIO) may be associated with a NAM response of the opposite sign. This study uses a coupled ocean{\textendash}atmosphere model to separate the influence on the NAM from teleconnections driven by ENSO and the TIO. In composites constructed using a long preindustrial control integration, increased December{\textendash}February precipitation in the central/eastern Pacific drives a negative late-winter NAM response. When isolated from ENSO variability, increased precipitation over the western-central TIO drives a strong and persistent positive NAM response throughout the winter. Opposite linear interference of the anomalous wave teleconnections explains most of the opposite-signed planetary wavedriving of the NAM responses. The case with combined ENSO and TIO variability yields cancellation of the wave interference and a weak NAM response. This mechanism is confirmed using experiments where the tropical ocean is nudged separately over the Pacific and TIO to the large-amplitude 1997/98{\textendash}1998/99 ENSO cycle. The phases of the Rossby wave and NAM responses in these two cases are of opposite sign, providing strong evidence that internal variability over the TIO can induce teleconnections independent of{\textemdash}and with opposite sign to{\textemdash}those associated with ENSO.},
	issn = {0894-8755},
	doi = {10.1175/JCLI-D-14-00839.1},
	url = {http://journals.ametsoc.org/doi/full/10.1175/JCLI-D-14-00839.1},
	author = {Fletcher, Christopher G. and Christophe Cassou}
}
@article {fletcher_evaluating_2015,
	title = {Evaluating biases in simulated snow albedo feedback in two generations of climate models},
	journal = {Journal of Geophysical Research: Atmospheres},
	year = {2015},
	pages = {n/a{\textendash}n/a},
	issn = {2169897X},
	doi = {10.1002/2014JD022546},
	url = {http://doi.wiley.com/10.1002/2014JD022546},
	author = {Fletcher, Christopher G. and Thackeray, Chad W. and Burgers, Tonya M.}
}
@article {fletcher_linear_2015,
	title = {Linear interference and the northern annular mode response to El Ni{\~n}o and climate change},
	journal = {Climate Dynamics},
	year = {2015},
	issn = {0930-7575, 1432-0894},
	doi = {10.1007/s00382-015-2518-0},
	url = {http://link.springer.com/10.1007/s00382-015-2518-0},
	author = {Fletcher, Christopher G. and Minokhin, Ivan}
}
@article {fletcher_projected_2015,
	title = {Projected changes in mid-21st century extreme maximum pavement temperature in Canada},
	journal = {Journal of Applied Meteorology and Climatology},
	year = {2015},
	abstract = {Future climate warming is virtually certain to bring about an increase in the frequency of heat extremes. Highway design and pavement selection are based on a temperature regime that reflects the local climate zone. Increasing heat extremes could, therefore, shift some areas into a different pavement grade (PG), and more heat-resistant materials are associated with increased infrastructure costs. This study combines observations, global climate model output, and a statistical model to investigate changes in 20-year return values of extreme maximum pavement temperature (TPmax). From a multimodel range of simulated TPmax, future changes in PG are computed for 17 major Canadian cities. Relative to a 1981-2000 baseline, summertime Canada-wide warming of 1-3{\textdegree}C is projected for the period 2041-70. As a result, climate change is likely to bring about profound changes to the spatial distribution of PG, with the severity of the changes directly linked to the severity of the projected warming. Even under weak simulated warming, an increase in PG is projected for Canada{\textquoteright}s largest urban area, the Greater Toronto Area, and under moderate (strong) warming 7 out of 17 (9 out of 17) major cities exhibit an increase. The influence of model spatial resolution is evaluated by comparing the results from global climate models with output from a set of regional climate models focused on North America. With the exception of mountainous terrain in western Canada, spatial resolution is not a major determining factor for projections of future PG changes.},
	issn = {1558-8424},
	doi = {10.1175/JAMC-D-15-0232.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/JAMC-D-15-0232.1},
	author = {Fletcher, Christopher G. and Matthews, Lindsay and Andrey, Jean and Saunders, Adam}
}
@article {thackeray_quantifying_2015,
	title = {Quantifying the skill of CMIP5 models in simulating seasonal albedo and snow cover evolution: CMIP5 simulated albedo and SCF skill},
	journal = {Journal of Geophysical Research: Atmospheres},
	year = {2015},
	pages = {n/a{\textendash}n/a},
	issn = {2169897X},
	doi = {10.1002/2015JD023325},
	url = {http://doi.wiley.com/10.1002/2015JD023325},
	author = {Thackeray, Chad W. and Fletcher, Christopher G. and Derksen, Chris}
}
@article {thackeray_influence_2014,
	title = {The influence of canopy snow parameterizations on snow albedo feedback in boreal forest regions: Boreal forest snow albedo feedback},
	journal = {Journal of Geophysical Research: Atmospheres},
	volume = {119},
	year = {2014},
	pages = {9810{\textendash}9821},
	issn = {2169897X},
	doi = {10.1002/2014JD021858},
	url = {http://doi.wiley.com/10.1002/2014JD021858},
	author = {Thackeray, Chad W. and Fletcher, Christopher G. and Derksen, Chris}
}
@article {fletcher_linear_2013-1,
	title = {Linear interference and the Northern Annular Mode response to tropical SST forcing: Sensitivity to model configuration},
	journal = {Journal of Geophysical Research: Atmospheres},
	volume = {118},
	year = {2013},
	pages = {4267{\textendash}4279},
	abstract = {Interannual variability in tropical sea surface temperatures (SSTs) associated with the El Ni{\~n}o{\textendash}Southern Oscillation is linked to teleconnections with the Northern Annular Mode (NAM). Previous work highlighted that the sign and amplitude of the NAM response to tropical SSTs are controlled by the total wave activity entering the subpolar stratosphere, which depends on the linear interference of planetary wave anomalies with the climatological stationary wave field. This study uses multiple configurations of atmospheric general circulation models to assess the robustness of these linkages to details of the tropical SST forcing and model configuration. Across 23 cases with idealized SST forcing, the amplitudes of the tropical and extratropical wave responses are found to scale approximately linearly with forcing strength. But wave amplitude alone is not sufficient to predict the NAM response. Instead, the spatial structure of the wave response (and hence the linear interference) provides the best explanation of the NAM response in all cases. Linear interference explains most of the total wave activity response even in cases with stronger nonlinear contributions, due to consistent cancellation between quasi-stationary wave nonlinearity and nonlinearity arising from transient waves. Within this limited set of experiments, there is no evidence for a consistent sensitivity of the NAM response to horizontal resolution or to vertical resolution in the stratosphere. These findings reveal that linear interference provides a robust and reproducible mechanism linking midlatitude wave responses to zonal mean circulation (NAM) responses across a wide variety of forcing cases.},
	issn = {2169-8996},
	doi = {10.1002/jgrd.50385},
	url = {http://onlinelibrary.wiley.com/doi/10.1002/jgrd.50385/abstract},
	author = {Fletcher, Christopher G. and Kushner, Paul J.}
}
@article {hambly_projected_2013,
	title = {Projected implications of climate change for road safety in Greater Vancouver, Canada},
	journal = {Climatic Change},
	volume = {116},
	year = {2013},
	pages = {613{\textendash}629},
	issn = {0165-0009, 1573-1480},
	doi = {10.1007/s10584-012-0499-0},
	url = {http://link.springer.com/10.1007/s10584-012-0499-0},
	author = {Hambly, Derrick and Andrey, Jean and Mills, Brian and Fletcher, Chris}
}
@article {lawrence_ccsm4_2012,
	title = {The CCSM4 Land Simulation, 1850{\textendash}2005: Assessment of Surface Climate and New Capabilities},
	journal = {Journal of Climate},
	volume = {25},
	year = {2012},
	pages = {2240{\textendash}2260},
	issn = {0894-8755, 1520-0442},
	doi = {10.1175/JCLI-D-11-00103.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00103.1?journalCode=clim},
	author = {Lawrence, David M. and Oleson, Keith W. and Flanner, Mark G. and Fletcher, Christopher G. and Lawrence, Peter J. and Levis, Samuel and Swenson, Sean C. and Bonan, Gordon B.}
}
@article {fletcher_using_2012,
	title = {Using models and satellite observations to evaluate the strength of snow albedo feedback},
	journal = {Journal of Geophysical Research: Atmospheres},
	volume = {117},
	year = {2012},
	pages = {D11117},
	abstract = {Snow albedo feedback (SAF) is important for global climate change, with strong regional impacts over northern continental areas. SAF calculated from the seasonal cycle is a good predictor of SAF in climate change among a suite of coupled climate models. A previous linear decomposition of the simulated total SAF (NET) found 80\% was related to the albedo contrast of snow covered and snow-free land (SNC), and 20\% was related to the temperature dependence of snow albedo (TEM). By contrast, recent work using snow cover and surface albedo derived from APP-x satellite observations found that TEM and SNC contributed almost equally to NET. In the present study, revised estimates of TEM and SNC for northern land areas are calculated for the period 1982{\textendash}99 using a simplified and reproducible method for comparing SAF in models and observations. The observed NET is -1.11\% K-1, of which 69\% comes from SNC and 31\% from TEM; the approximate additivity of SNC and TEM indicates that these two terms fully explain the total SAF. Regionally, the SNC term dominates equatorward of 65{\textdegree}N, while TEM dominates over the Arctic. The mean of 17 CMIP3 climate models shows NET is 7\% larger than observed, caused primarily by a bias in TEM equatorward of 65{\textdegree}N. A newer model (NCAR CCSM4) with improved land surface and snow schemes reproduces observed values of NET and SNC closely. However, TEM in all models examined is 50{\textendash}100\% weaker than observed over the Arctic. There is a strong correlation between SAF in the seasonal cycle and SAF in climate change for all components, but the correlation is weakest for TEM. The TEM term also exhibits a much larger spread in the seasonal cycle than in climate change, which partially explains a discrepancy between previous published studies examining TEM.},
	issn = {2156-2202},
	doi = {10.1029/2012JD017724},
	url = {http://onlinelibrary.wiley.com/doi/10.1029/2012JD017724/abstract},
	author = {Fletcher, Christopher G. and Zhao, Hongxu and Kushner, Paul J. and Fernandes, Richard}
}
@article {derksen_variability_2012,
	title = {Variability and change in the Canadian cryosphere},
	journal = {Climatic Change},
	volume = {115},
	year = {2012},
	note = {WOS:000309866900004},
	pages = {59{\textendash}88},
	abstract = {During the International Polar Year (IPY), comprehensive observational research programs were undertaken to increase our understanding of the Canadian polar cryosphere response to a changing climate. Cryospheric components considered were snow, permafrost, sea ice, freshwater ice, glaciers and ice shelves. Enhancement of conventional observing systems and retrieval algorithms for satellite measurements facilitated development of a snapshot of current cryospheric conditions, providing a baseline against which future change can be assessed. Key findings include: 1. surface air temperatures across the Canadian Arctic exhibit a warming trend in all seasons over the past 40 years. A consistent pan-cryospheric response to these warming temperatures is evident through the analysis of multi-decadal datasets; 2. in recent years (including the IPY period) a higher rate of change was observed compared to previous decades including warming permafrost, reduction in snow cover extent and duration, reduction in summer sea ice extent, increased mass loss from glaciers, and thinning and break-up of the remaining Canadian ice shelves. These changes illustrate both a reduction in the spatial extent and mass of the cryosphere and an increase in the temporal persistence of melt related parameters. The observed changes in the cryosphere have important implications for human activity including the close ties of northerners to the land, access to northern regions for natural resource development, and the integrity of northern infrastructure.},
	issn = {0165-0009},
	doi = {10.1007/s10584-012-0470-0},
	author = {Derksen, C. and Smith, S. L. and Sharp, M. and Brown, L. and Howell, S. and Copland, L. and Mueller, D. R. and Gauthier, Y. and Fletcher, C. G. and Tivy, A. and Bernier, M. and Bourgeois, J. and Brown, R. and Burn, C. R. and Duguay, C. and Kushner, P. and Langlois, A. and Lewkowicz, A. G. and Royer, A. and Walker, A.}
}
@article {fletcher_role_2011,
	title = {The Role of Linear Interference in the Annular Mode Response to Tropical SST Forcing},
	journal = {Journal of Climate},
	volume = {24},
	year = {2011},
	pages = {778{\textendash}794},
	issn = {0894-8755, 1520-0442},
	doi = {10.1175/2010JCLI3735.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3735.1},
	author = {Fletcher, Christopher G. and Kushner, Paul J.}
}
@article {smith_role_2010,
	title = {The Role of Linear Interference in the Annular Mode Response to Extratropical Surface Forcing},
	journal = {Journal of Climate},
	volume = {23},
	year = {2010},
	pages = {6036{\textendash}6050},
	issn = {0894-8755},
	doi = {10.1175/2010JCLI3606.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3606.1},
	author = {Smith, Karen L. and Fletcher, Christopher G. and Kushner, Paul J.}
}
@article {fletcher_circulation_2009,
	title = {Circulation responses to snow albedo feedback in climate change},
	journal = {Geophysical Research Letters},
	volume = {36},
	year = {2009},
	pages = {L09702},
	abstract = {Climate change is expected to cause a reduction in the spatial extent of snow cover on land. Recent work suggests that this will exert a local influence on the atmosphere and the hydrology of snow-margin areas through the snow-albedo feedback (SAF) mechanism. A significant fraction of variability among IPCC AR4 general circulation model (GCM) predictions for future summertime climate change over these areas is related to the models{\textquoteright} representation of springtime SAF. In this study, we demonstrate a nonlocal influence of SAF on the summertime circulation in the extratropical Northern Hemisphere. Increased land surface warming in models with stronger SAF is associated with large-scale sea-level pressure anomalies over the northern oceans and a poleward intensified subtropical jet. We find that up to 25{\textendash}30\% and, on average, 5{\textendash}10\% of the inter-model spread in projections of the circulation response to climate change is linearly related to SAF strength.},
	issn = {1944-8007},
	doi = {10.1029/2009GL038011},
	url = {http://onlinelibrary.wiley.com/doi/10.1029/2009GL038011/abstract},
	author = {Fletcher, Christopher G. and Kushner, Paul J. and Hall, Alex and Qu, Xin}
}
@article {fletcher_dynamical_2009,
	title = {The Dynamical Response to Snow Cover Perturbations in a Large Ensemble of Atmospheric GCM Integrations},
	journal = {Journal of Climate},
	volume = {22},
	year = {2009},
	pages = {1208{\textendash}1222},
	issn = {0894-8755, 1520-0442},
	doi = {10.1175/2008JCLI2505.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/2008JCLI2505.1},
	author = {Fletcher, Christopher G. and Hardiman, Steven C. and Kushner, Paul J. and Cohen, Judah}
}
@article {cohen_improved_2007,
	title = {Improved Skill of Northern Hemisphere Winter Surface Temperature Predictions Based on Land{\textendash}Atmosphere Fall Anomalies},
	journal = {Journal of Climate},
	volume = {20},
	year = {2007},
	pages = {4118{\textendash}4132},
	issn = {0894-8755, 1520-0442},
	doi = {10.1175/JCLI4241.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/JCLI4241.1},
	author = {Cohen, Judah and Fletcher, Christopher}
}
@article {fletcher_stratospheric_2007,
	title = {Stratospheric control of the extratropical circulation response to surface forcing},
	journal = {Geophysical Research Letters},
	volume = {34},
	year = {2007},
	issn = {0094-8276},
	doi = {10.1029/2007GL031626},
	url = {http://doi.wiley.com/10.1029/2007GL031626},
	author = {Fletcher, Christopher G. and Kushner, Paul J. and Cohen, Judah}
}
@article {fletcher_winter_2006,
	title = {Winter North Atlantic Oscillation Hindcast Skill: 1900{\textendash}2001},
	journal = {Journal of Climate},
	volume = {19},
	year = {2006},
	pages = {5762{\textendash}5776},
	abstract = {Abstract Recent proposed seasonal hindcast skill estimates for the winter North Atlantic Oscillation (NAO) are derived from different lagged predictors, NAO indices, skill assessment periods, and skill validation methodologies. This creates confusion concerning what is the best-lagged predictor of the winter NAO. To rectify this situation, a standardized comparison of NAO cross-validated hindcast skill is performed against three NAO indices over three extended periods (1900{\textendash}2001, 1950{\textendash}2001, and 1972{\textendash}2001). The lagged predictors comprise four previously published predictors involving anomalies in North Atlantic sea surface temperature (SST), Northern Hemisphere (NH) snow cover, and an additional predictor, an index of NH subpolar summer air temperature (TSP). Significant (p textless 0.05) NAO hindcast skill is found with May SST 1900{\textendash}2001, summer/autumn SST 1950{\textendash}2001, and warm season snow cover 1972{\textendash}2001. However, the highest and most significant hindcast skill for all periods and all NAO indices is achieved with TSP. Hindcast skill is nonstationary using all predictors and is highest during 1972{\textendash}2001 with a TSP correlation skill of 0.59 and a mean-squared skill score of 35\%. Observational evidence is presented to support a dynamical link between summer TSP and the winter NAO. Summer TSP is associated with a contemporaneous midlatitude zonal wind anomaly. This leads a pattern of North Atlantic SST that persists through autumn. Autumn SSTs may force a direct thermal NAO response or initiate a response via a third variable. These findings suggest that the NH subpolar regions may provide additional winter NAO lagged predictability alongside the midlatitudes and the Tropics.},
	issn = {0894-8755},
	doi = {10.1175/JCLI3949.1},
	url = {http://journals.ametsoc.org/doi/abs/10.1175/JCLI3949.1},
	author = {Fletcher, Christopher G. and Saunders, Mark A.}
}
