Resource Category: Journal Papers and Book Chapters

We analyzed annual peak flow series from 127 naturally flowing or naturalized streamflow gauges
across western Canada to examine the impact of the Pacific Decadal Oscillation (PDO) on annual flood risk,
which has been previously unexamined in detail. Using Spearman’s rank correlation q and permutation tests on
quantile-quantile plots, we show that higher magnitude floods are more likely during the negative phase of the
PDO than during the positive phase (shown at 38% of the stations by Spearman’s rank correlations and at 51%
of the stations according to the permutation tests).

We analyzed annual peak flow series from 127 naturally flowing or naturalized streamflow gauges
across western Canada to examine the impact of the Pacific Decadal Oscillation (PDO) on annual flood risk,
which has been previously unexamined in detail. Using Spearman’s rank correlation q and permutation tests on
quantile-quantile plots, we show that higher magnitude floods are more likely during the negative phase of the
PDO than during the positive phase (shown at 38% of the stations by Spearman’s rank correlations and at 51%
of the stations according to the permutation tests).

Annual area burned (AAB) variability in northwestern North America was inferred from 38 treering width chronologies widely distributed across boreal regions and spanning the past 300 years and the minimum 1833–1998 interval. AAB estimates accounted for up to 61% of the variance in AAB observed from 1959
to 1998, and were verified using a split sample calibration-verification scheme. Spatial correlation maps of gridded temperature and precipitation data provided an indication of the reliability of the reconstruction to approximate fire-conducive climate variability beyond the period of calibration.

Streamflow in South-Central Chile (SCC, ⇠35oS-42oS) is vital for
agriculture, forestry production, hydroelectricity, and human consumption.
Recent drought episodes have generated hydrological deficits with damaging
e↵ects on these activities. This region is projected to undergo major reductions
in water availability, concomitant with projected increases in water demand.

This paper discusses ways in which the tree-ring-based reconstruction of paleohydrology can
be better understood and better utilized to support water resource management, especially in cold semiarid
regions. The relationships between tree growth as represented by tree ring chronologies (TRCs), runoff (Q),
precipitation (P), and evapotranspiration (ET) are discussed and analyzed within both statistical and
hydrological contexts.

Canada is perceived by many to be water-rich, yet renewable fresh water supply is a
limiting factor. The southern, most-populated region of the country has about “2.6 percent
of the world water supply”(Sprague, 2007, p. 25). Semi-arid areas experience water
shortages, and increasing demands for water have led to moratoriums in water allocations.

Changing hydroclimatic conditions on the Canadian Prairies include significant
shifts in the intensity, duration, and frequency of precipitation events, as well as temperature
and seasonal shifts that affect water availability and quality. Concurrently, high-water-useintensity industrial development, such as solution potash mining, is also lessening availability
of timely water resources in agricultural regions and southern Prairie watersheds.

Since human activities and ecosystem health require adequate, reliable water supplies, hydro-climatic variability
and extremes pose serious threats to society and the environment. Previous studies have shown that the Canadian Prairies
normally experience considerable hydro-climatic variability, including periodic droughts and excessive moisture conditions,
which are mainly caused by mid-tropospheric circulations that disrupt expected precipitation and temperature patterns.

This study describes the development of 13 moisture-sensitive tree-ring chronologies from the
Churchill River Basin of northern Saskatchewan, and their application to estimate streamflow prior to
the initiation of direct monitoring in 1929. Most of these new tree-ring records extend back to the early
or mid-19th century, with their length limited by the lifespan of trees growing in fire-dominated boreal
forest environments. Ring-width index chronologies are significantly correlated with mean annual and
summer streamflow across the watershed; those records that were highly (above 0.6) correlated with
streamflow were chosen as potential predictors in linear regression models.

We present a simplified overview of land-atmosphere feedbacks at interannual timescales over tropical South America as structural sets of linkages among surface air temperature (T), specific humidity at 925 hPa (q925), volumetric soil water content (Θ), precipitation (P), and evaporation (E), at monthly scale during 1979–2010. Applying a Maximum Covariance Analysis (MCA), we identify
the modes of greatest interannual covariability in the datasets.