Time series of weighted mean areal PDSI for each drought decade. In Hoover’s drought relief plan, a national committee was set up to coordinate state committees, which would in turn organize committees in each county. The site monitors the risk and status of drought over major agricultural regions of the country and also promotes practices to reduce drought vulnerability.

McGraw Hill, 508 pp. Both decades enjoyed a recovery from drought conditions around the midpoint of their respective decades, but the decade with the more intense events (the 1980s) experienced a much stronger recovery.

Hare, F. K., 1977: Climate and desertification. Agron. 1984), but to our knowledge those results have not been applied simultaneously to the 1930s and the 1980s to search out differences in drought patterns. The area of low precipitation normally found south of the storm tracks shifted farther south and exacerbated dryness in the area. These interviews would later form the core of Gray’s influential book on the dustbowl, Men Against the Desert. Recovery was also weaker than the 1980s. Mean annual precipitation within the study area. The droughts of the 1930s and 1980s were not unique to the southern prairies. A full treatment of the PDSI, including modifications by Alley (1984), is covered in Weber and Nkemdirim (1994, 1998).

Local droughts of shorter duration have occurred since then in parts of Canada, especially in the Prairies (late 1950s/early 1960s, 1980s and 1999-2005). The combination of poor harvests and low … [Available from Atmospheric Environment Service, 4905 Dufferin St., Toronto, ON M3H 5T4, Canada. and Wheaton, E. 1995.

The number of immigrants accepted into Canada dropped from 169,000 in 1929 to fewer than 12,000 by 1935. We conclude from the PDSI patterns that the drought dynamics were different. While the 1980s had, on average, slightly more area in the most extreme drought category, the total percentage of area in classifications up to class 6 (PDSI < 0) was greater during the 1930s. In 1981, 1983, 1984, 1985, and 1986, it ranged from 73% to 68% of normal.

Geograph., 43, 19–30.

Areas with greater drought risks are often better prepared to deal with dry conditions. The ratio of actual to potential evaporation (α) averages 85% annually in the study area. Reduced precipitation along the wet zone further suggests that the cyclones did not carry significant amounts of moisture into the region. Jones, K. H., 1984: An evaluation of the Palmer drought index in southern Saskatchewan. Three decades, 1910–20, 1930–39, and 1980–89, however, stand out as dry because at least half their length was drought stricken. But more water is being drawn from them for cities, irrigation and the processing of oil from tar sands. They don’t read like typical academic articles or books. We were excited at the prospect of producing a synthesis building on recent scholarship focused on the human and environmental histories of the Canadian prairies in the 1930s. It was structured to combine central coordination with local units staffed by local citizens. In areas where irrigation water is available and stored water supplies ample, a meteorological drought may not lead to an agricultural drought. Amer. 2). This type of drought can be defined as an unusual shortage of water that produces an adverse effect on society and the economy. 2. Bonsal, B.R., Shabbar, A. and Higuchi, K. 2001. Vol. Prolonged, large-area droughts are among Canada's costliest natural disasters having major impacts on a wide range of sectors including agriculture, forestry, industry, municipalities, recreation, human health, society and ecosystems. However, this did not compromise the severity of the second half-drought of the 1980s, suggesting that without the generous recovery, the second series of runs would have been much worse.

1993. Three successive crop failures in 1929, 1930, and 1931, with yields of 70–150 kg ha−1, were attributed to lack of timely rainfall. Worse, such conditions may become the norm. (1986) that produced results that agreed well with Hengevold’s (1991) estimates for Canadian cities. The years 2001 and 2002 may have also brought the first coast-to-coast droughts on record, and were rare as they struck areas less accustomed to dealing with droughts including parts of Atlantic Canada and the northern agricultural prairies (see Figure 1).

Water Resour. They found, however, that for shorter duration events, in the order of one year or less, variations in PDSI calculated with different values of AWC were not statistically significant. PDSI was computed for each station for 1927 through 1996. Zhang, X., Harvey, K.D., Hogg, W.D. The causes of blocking and other flow conditions that lead to drought are not yet understood. It extends from Lake Winnipeg to the east to the Alberta border in the west (Fig. Because the study region is precariously wedged between two zones, one with reliable precipitation to the north, and the other a drier and less reliable precipitation zone to the south, any significant shift in atmospheric circulation patterns can bring it either into a moister regime or a drier one. Lower levels coincided with the droughts of the 1930s, early 1960s, and the recent 1999-2001 dry period. Extreme drought conditions returned in 1936, 1939 and 1940. The slightly greater mean drought severity of the 1929–39 series discussed earlier is confirmed. Borchert (1953) showed by means of streamlines of resultant airflow at the geostrophic wind level that dry continental air dominates the area bounded by the Alberta storm track and the 100th meridian and the U.S. border in July. van Bavel, C. H. M., 1953: A drought criterion and its applications in evaluating drought incidence and hazard. [Editors note: this post was prepared for both our website and NiCHE-Canada.org where it was published on Monday, November 28, 2016]. In general, the region consists of a gently sloping plain, rising from a low 200 m above sea level in the Lake Winnipeg area to more than 1800 m in the foothills of the Rockies west of Calgary. The stations were subsequently divided into groups such that stations within groups shared more in common than they did with those in adjacent groups, a quality achieved through analyses of correlations and variances.

Drought is the condition of critically low water supply caused by persistently below-normal precipitation.

They found that while the droughts of 1987–88 were more widespread than those of 1937–38, the actual cumulative precipitation deficit did not suggest which drought was more intense.