Regarding the drought continuing through this winter and spring, everyone is watching what appears to be a new La Niña developing, Nielsen-Gammon said.
But a strong Pacific Ocean La Niña is not the only phenomenon that affects Texas droughts, he said. Scientists now believe that Atlantic Ocean temperature oscillations also play a role in long-term droughts such as the one that hammered Texas and the Midwest in the middle of the last century.
Two-minute MP3 Audio Texas crop, weather report for Oct. 4, 2011
Climatologists have found a strong correlation between Pacific Ocean surface temperatures and some events like the Dust Bowl drought. But the drought of the 1950s, which rivaled the current drought, did not show up in the computer simulations correlated with Pacific Ocean La Niña events. The simulations did find, however, that patterns that strongly suggested warmer-than-average North Atlantic sea-surface temperatures also contributed to droughts in parts of North America, Texas included, according to Nielsen-Gammon.
“Compared to the trend, the north Atlantic is warm in the 1940s and ‘50s, cool in the 1970s and ‘80s, and warm since 1995,” he said. “A cool North Atlantic implies a wet North America, amplifying the response to an El Niño.”
According to similar study, drought in Texas has been overwhelmingly more frequent when there is a negative Pacific Ocean La Niña event and a warm North Atlantic, such as was in place during the 1950s.
All this may seem a bit esoteric to any but professional climatologist, Nielson-Gammon said, particularly as there is currently no proven way of forecasting long-term ocean variability in the Pacific or North Atlantic.
“We do know that the current temperature patterns are not a death sentence for non-stop drought,” Nielson-Gammon writes in his blog, The Climate Abyss. “But we have heightened drought susceptibility during this period, and, according to some studies, the effect of La Niña is likely to be amplified. … So this coming year looks very likely to be another dry one, and consequently it is very likely that next summer will have water shortages and drought problems even more severe than this summer.”
And what about the long-term picture?
“At this point, all I can say is that we’re in a period of frequent Texas drought until further notice,” he said. “This period, with both the Pacific and Atlantic working against us, might be over in a couple of years, or it might last another 15 or 20 years. It seems likely to last another decade.”
More information on the current Texas drought and wildfire alerts can be found on the AgriLife Extension Agricultural Drought Task Force website at http://agrilife.tamu.edu/drought/ .
AgriLife Extension district reporters compiled the following summaries:
Central: Conditions were extremely dry. Hay supplies continued to be tight, and — with no available forages — livestock producers further culled herds. Several counties saw light scattered showers but did not receive enough rain to provide drought relief.Coastal Bend: The region had isolated showers, but much more rain was needed to replenish parched soils and to promote forage growth in pastures and hay meadows. Livestock producers were concerned about very short hay supplies going into fall and winter, and were reducing herd sizes. The production of cool season crops may not be possible due to the drought. In Washington County, livestock sales continued, as did supplemental feeding and watering of livestock. Many ponds were being renovated while they were dry. Many trees were dying or dead. Some producers were planting winter pastures. In Nueces County, growers finished harvesting sesame.
East: The drought continued with little to no rain received. Many producers hesitated planting winter pastures because of dry soils. The few that were planting were doing so in river bottoms and lower-lying land. Large numbers of cattle flowed through the sale barns as producers continued to sell off cattle or sell out herds entirely. Panola County reported a more than a 50 percent drop in the number of cattle in the area, and Trinity County reported a 30 percent to 40 percent drop. Feral hog damage increased.
Far West: Scattered showers visited the area, but left behind only traces or sprinkles. Presidio and Brewster counties were the exceptions, with reports of 0.2 to 0.5 inch of rain. The danger of wildfire remained high due to lightening in passing cool fronts. Most Brewster County livestock producers were still repairing or replacing fences burned this year as they prepared for fall working of cattle or shipping of stockers. In Brewster and Jeff Davis counties, producers were selling brood cows because of the drought and wildfire having burned over 800,000 acres of rangeland. Rangeland and pastures were in very poor, dry condition. In El Paso County, the pecan crop was ahead of average maturity by about 10 days. Alfalfa producers were taking the last cutting of the season, and cotton was ready for defoliation. More advanced cotton fields had 50 percent of bolls open. Some producers were still feeding and supplementing cattle while others continued to sell some or all. Red Bluff reservoir engineers stopped sending water down the canals due to low water levels, putting alfalfa producers in a sticky situation. Without irrigation water, portions of fields that are dying cannot be replanted. The Andrews County pecan crop was in fair condition.
North: The region had cooler temperatures but received little or no rain. Soils remained very dry. Rangeland and pastures were poor to very poor condition. A few farmers have began planting small grains and winter pastures and were praying for rain. Some ranchers were buying hay from northern and northeastern states, but the transportation costs make it very expensive. Large numbers of cows were going through sale barns. Even those cattlemen who had hoped to hold onto their core animals were starting to sell out. Livestock water was becoming critical, with most stock-watering ponds very low or completely dry.
Panhandle: The region remained dry with above-average temperatures. Soil-moisture levels were very short. A few isolated areas received from a trace to 0.9 inches of rain. The corn harvest was ongoing with below-average yields. Most corn had been abandoned earlier in the summer and some was cut for hay. The soybean harvest continued. Cotton growers in some areas were applying harvest aids. Winter wheat was being planted. Rangeland and pastures were in very poor condition. Livestock producers continued supplemental feeding of cattle.
Rolling Plains: Dry conditions persisted. Temperatures rose, with highs in the mid-90s in some areas. Pastures and rangeland were in very poor condition. Beef cattle producers and horse owners were still looking for hay. Producers increased culling strategies on cattle herds. Some producers were planting wheat in hopes of some moisture to get it sprouted. Earlier planted wheat that germinated had very spotty stands with heavy weed pressure. Wildfires remained a big threat. Approximately 10,000 acres burned in Foard County during the last two weeks. The fires were started by lightning strikes. Burn bans remained in effect.
South: Soil moisture conditions were short to very short throughout the region. A cool front brought some showers that slightly improved rangeland and pastures. Parts of Frio County received about half an inch, while some La Salle County areas received about 2 inches. However, mostly all the rain did was bring cooler weather. Rangeland and pastures still needed a lot of rain to recover from the damaged done by drought. Livestock producers were culling more cattle and providing supplemental feed at a steady rate. Producers continued to have problems finding hay. Peanuts were progressing well and showing signs of making a good crop. In Atascosa and Frio counties, oats and ryegrass planted a week earlier had already sprouted. In Zavala County, cotton gins were busy and had a lot of cotton modules in site. Also in that area, some producers began planting spinach. Irrigated oats and wheat fields were already planted. In Hidalgo County, sugarcane growers were preparing for harvest, and early maturing citrus harvesting was under way.
South Plains: Dry conditions continued, with a few areas getting showers. Cotton growers began harvesting, as did growers of corn, sorghum and pumpkins. Pumpkin yields were about 50 percent of average. Temperatures were in upper 80s to mid-90s.
Southeast: Parts of Montgomery County received less than a half inch of rain, making the area more than 30 inches behind for the year. In Burleson County, a few optimistic livestock owners were drilling oats. Brazoria County had scattered showers, with accumulations ranging from 0.1 to 0.75 inch. Rice growers were concerned whether they’ll have irrigation water for the 2012 crop. Row-crop producers were concerned if they’ll have enough soil moisture for spring planting. Cattle producers continued to cull herds, while trying to feed some of their remaining cattle. Hay supplies were very short. Without rain, farm ponds continued to dry out.
Southwest: Some areas received scattered rains and cooler temperatures, but extremely dry conditions generally prevailed. Livestock producers continued to provide supplemental feed to cattle or to liquidate herds. There was little or no sign of appreciable forage growth. Some producers were preparing to plant winter pastures.
West Central: The region had warm days with continued extremely dry conditions. Nighttime temperatures were cooled. A few areas reported scattered showers. The wildfire danger remained extremely high. Soil-moisture levels were very low. Wheat planting was under way, with most being planted into dry soils. A few producers were planning to plant some form of cool-season forage in hopes it will rain soon. There was no improvement of rangeland and pasture conditions. All water sources were dropping. Livestock producers increased supplemental feeding of cattle or liquidation of herds.
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