Coping with Drought

Groundwater measurement as drought indicator in Southeast
In the Southeast, large seasonal to inter-annual climate variability that causes frequent droughts is considered to be greatly influenced by El Niño Southern Oscillation (ENSO). El Niño years tend to be cool and wet, while La Niña years tend to be warm and dry between October and April.

Differences in groundwater level anomalies produced by El Niño and La Niña phases during (a) recharge (October to April) and (b) non-recharge (May-September) seasons in the study area. This study area makes the lower portion of the ACF River Basin. The polygons are geo-hydrologic zones.

Differences in groundwater level anomalies produced by El Niño and La Niña phases during (a) recharge (October to April) and (b) non-recharge (May-September) seasons in the study area. This study area makes the lower portion of the ACF River Basin. The polygons are geo-hydrologic zones.

Read more in Dry Times, Nov 2014, Volume 4 Issue 2 (pages 10-11)

 

Climate information use among southeast US water managers: beyond barriers and toward opportunities
Despite nearly 20 years of work on understanding the climate information needs of stakeholders and simultaneous development of decision support tools, a relatively low level of awareness of specific climate information products exists among many water managers in the southeastern United States. This paper presents results from an assessment among water managers in Alabama, Florida, and Georgia of awareness, perception, barriers, and opportunities associated with utilizing climate information.

 

 

Decisions made across timescales. Coded responses to open-ended question, ‘‘At which of the following time scales do decisions and planning occur at your agency? Please check as many as apply and list the types of decisions/planning that occur at each time scale.’’

Decisions made across timescales. Coded responses to open-ended question, ‘‘At which of the following time scales do decisions and planning occur at your agency? Please check as many as apply and list the types of decisions/planning that occur at each time scale.’’

Read more in Regional Environmental Change, Aug 2013, Volume 13 Issue 1 (pp 141-151)

 

City Uses Climate Information for Drought Preparedness
As part of a Southeast Climate Consortium (SECC) initiative and as a result of a 2007-2008 drought in the Southeast US, we started working with the City of Auburn, AL to see how the city was dealing with the water supply and demand issues during drought. ..

…When SECC started working with Auburn, the city was not using SI climate forecasts for their water supply and demand management. We worked with the city’s Watershed Division Manager, Matthew Dunn, and discussed with him how to use SI climate forecasts to reduce the impact of drought on water supply and demand.

drought_prepare[1]

 

Read more in NIDIS Drought Research Special Issue, Fall 2011, Volume 2 Issue 2 (page 5)

Decadal, inter-decadal climate variability modulate droughts
Study of large-scale climate phenomena as well as the interactions of interannual with decadal and multidecadal oceanic-atmospheric phenomena can provide valuable information regarding regional climatic conditions such as droughts and their impact on water resources. This study was conducted to quantify the impacts of climate variability cycles on baseflow levels in the Flint River. The impacts of the El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), and North Atlantic Oscillation (NAO) on baseflow were studied.

dr srivastava's report

Box and whisker plots of the percent increase/decrease in baseflows for Flint River. The boundaries of the box represent the first (Q1) and third (Q3) quartiles and the whiskers extend from the boundaries of the box to the extreme data points which are no more than 1.5 times the interquartile range (Q3 – Q1).

Read more in Dry Times, Nov 2015, Volume 5 Issue 2 (Page 4)

Effect of irrigation pumpage during drought on karst aquifer systems in highly agricultural watersheds:
A simulation model was used to understand and quantify the effect of irrigation pumpage on the groundwater supply in Southwest Georgia for two different drought years: moderate and severe. Comparison of irrigated and non-irrigated scenarios showed that groundwater discharge to streams is a major outflow from the aquifer, and irrigation can cause as much as 10% change in river-aquifer flux. The study suggests that improved groundwater withdrawal strategies using climate forecasts needs to be developed in such a way that excessive withdrawals during droughts can be reduced to protect streams and river flows.

Effect of irrigation pumpage during drought on karst aquifer (image)

Percentage changes in simulated recharge and discharge components due to irrigation pumpage for water year 2011. I and NI represents irrigated and non-irrigated scenarios, respectively.

Click here to read more
Mitra, S., P. Srivastava, and S. Singh. 2016. Effect of irrigation pumpage during drought on karst aquifer systems in highly agricultural watersheds: example of the Apalachicola-Chattahoochee-Flint river basin, southeastern USA. Hydrogeology Journal (In Press).

Development of Community Water Deficit Index: Drought-Forecasting Tool for Small- to Mid-Size Communities of the Southeastern United States
Although currently available drought indices can be useful tools for monitoring and forecasting purposes, they are not suitable for use in water-supply systems for small- to mid-size communities. Because small- to mid-size communities are most vulnerable to climate variability, this study was undertaken to develop a climate variability–based community water deficit index (CWDI) for use by water managers in these communities. The results indicate that the index not only can monitor drought in the studied water-supply systems, but can also forecast ENSO-induced hydrologic droughts in the region and can be used in drought planning.

Drought Deficit

Framework of the model showing (a) input data and modules of the STELLA model; (b) framework of the forecasting module; (c) some example modules as implemented in the CWDI STELLA model; GIS = geographic information system

Click here to read more
Sharda, V., P. Srivastava, L. Kalin, K. Ingram, and M. Chelliah. 2013. Development of Community Water Deficit Index: Drought-Forecasting Tool for Small- to Mid-Size Communities of the Southeastern United States. Journal of Hydrologic Engineering, 18(7): 846-858.