(California Snow Pack for January 18 2013 vs the California Snow Pack for January 18 2014. Note the near-zero snow cover for this drought-impacted region. Image source: NASA/Lance-Modis)
“We are on track for having the worst drought in 500 years.” — B. Lynn Ingram, professor of earth and planetary sciences at the University of California, Berkeley.
Remember the historic drought that swept the US in 2011-2013? It was the worse drought in 50 years for some areas. Thankfully, the blocking pattern, excess heat and evaporation that set off this drought and that almost ran the Mississippi River dry abated and lessened, shifting westward and, instead delivered wave after wave of wet and stormy weather to the Eastern US.
Not so with the American West. There the high amplitude Jet Stream pattern remained, keeping regions locked in warm, dry conditions throughout the winter of 2012-2013, on through the end of 2013 and into the early months of 2014.
Looking further back, it was not just these years that had delivered dry weather to the US West Coast. California, ground zero for the current climate change related emergency, has endured dry, hot weather ever since the Pacific Decadal Oscillation (PDO) went negative ten years ago suffering drought years with almost bi-annual frequency.
Now, as Dr. Ingram notes above, California is currently ramping up to its worst drought in 500 years.
A long emergency for California
We only have to scratch the surface for the symptoms of systemic climate crisis in California to crop up. California water authorities failed to honor contracts for the first time in 54 years. Sacramento, as of December was experiencing its worst drought in 130 years even as conditions continued to worsen through January and February.
According to the New York Times, as of February 1rst, 40,000 people were at risk of losing access to water within the next 60 to 120 days. And State officials warned that this number was likely to rapidly rise as The State Water Project announced on January 31rst that it did not have enough water to supplement the fading supplies of local providers to a total of 25 million customers. Meanwhile, State emergency planners were laying out contingencies that included shipping water over land by truck to parched communities.
The drought is also having a devastating impact on local farmers with about 1/3 of California’s farmland expected to lay fallow, at least 25,000 farm laborers expected to be laid off work, and agricultural businesses expecting losses to mount into the tens of millions of dollars. Already, livestock owners in both New Mexico and California, unable to support their animals, have been forced to sell, as fields that used to support four foot high grass are brown and cracked.
Tim Quinn, executive director of the Association of California Water Agencies noted:
“I have experienced a really long career in this area, and my worry meter has never been this high. We are talking historical drought conditions, no supplies of water in many parts of the state. My industry’s job is to try to make sure that these kind of things never happen. And they are happening.”
Climate change, climate change, and climate change
Far flung and dynamic changes to the Earth System appear to have resulted in a variety of factors that have amplified the California drought. First, increasing global temperatures have amped up the rate at which water evaporates into the atmosphere by about 6%, this increased rate of evaporation results in more extreme conditions when heat and dryness do occur. So a drought that may last a year is likely to be even more intense, due to enhanced evaporation, than a comparable drought that occurred 50 or 100 years ago.
In addition, loss of sea ice, snow, and permafrost plays a key roll in re-shaping the Jet Stream. According to Dr. Jennifer Francis and other polar researchers, receding sea ice cover is likely to result in more powerful and long-lasting Rossby Wave type blocking patterns. This happens as more heat becomes concentrated in the polar regions, causing the Jet Stream to meander in great swoops and whirls. These large waves can become fixed into blocking patterns for extended periods. In the up-slope of these waves, warmth and heat predominate. In the trough or down-slope, stormy, wet and cool conditions prevail.
And just such a blocking pattern has dominated the US West Coast for 11 months running. The result is extraordinarily intense dryness, even during the rainy season of November through March.
(Image source: PNAS)
Sadly, according to climate models, we can expect this kind of dryness to intensify over the US Southwest as human caused global warming grows more extreme. A report conducted by PNAS in 2010 and authored by Seager and Vecchi confirmed other model findings that the US Southwest would continue to dry as the climate warmed — the upshot being that the wet season for the West would eventually evaporate.
Above, the PNAS drought model shows evaporation beginning to increase during the first two decades of the 21rst Century. Then, by about decade 2, precipitation rates rapidly fall and evaporation rates gradually rise through to 2100. The red line shows the compounding effects of evaporation increase and precipitation decrease over 24 separate climate model essays.
(Rossby Wave over West Coast Weakens. Image source: University of Washington)
It is worth noting that on a positive, and slightly hopeful, note, the current blocking pattern over the US West Coast and related Pacific Ocean waters has weakened somewhat. This should allow some moisture to flow into the parched west over the coming days and weeks. And, in the forecast, we do see a proper storm or two emerging from this new pattern. Unfortunately, we’d typically expect about 20-30 storms of this kind during a typical winter season and with March bringing in the end to this year’s rainy season, along with the northward retreat of the moisture flow, it appears likely that California will have to endure at least another 6 months of dry conditions before seeing any hope of major storms returning next fall/winter. A remote potential to say the least given both long-term trends and current conditions.
‘Like a microwave on full blast drying the Earth:’ drought, drought, and more drought
“The extra heat from the increase in heat trapping gases in the atmosphere over six months is equivalent to running a small microwave oven at full power for about half an hour over every square foot of the land under the drought. No wonder wild fires have increased! So climate change undoubtedly affects the intensity and duration of drought, and it has consequences.”
Under such conditions, we would expect both drought and wildfires to proliferate. And, in fact, this is exactly what we are seeing. As major wildfires impacted both California and Arctic Norway during winter time, Brazil, Turkey, China, Argentina and Australia were also all experiencing some of their worst or most intense droughts on record.
In Brazil, the least rain in two decades is spurring a cattle sell-off that would be very familiar to livestock farmers in California and New Mexico. The expected summer rains did not come and Brazil, a heavily meat-dependent nation was left with soaring food prices after the sell-off as stocks first surged, then plummeted. The epic drought for this region is also causing a number of other impact such as coffee shortages and a related reduction in hydro power as rivers run dry.
Nearby Argentina also saw severe drought-related shocks in recent months as a December drought inflicted serious harm upon Argentina’s corn crop. In a typical year, Argentina produces about 32 million tons of corn. But this year’s drought is estimated to have wiped out about between 7 and 14 million tons of the crop. Argentina is the third largest producer of corn and with the US revising estimates down for its 2013-2014 crop, supplies of the grain are being drawn ever-lower. Though very intense, the December drought had abated by mid-January, providing a respite for other crops such as soybeans.
In Turkey, Lake Sapanca, which provides water for hundreds of adjacent farms, was within a half meter of ‘dying’ as a combination of drought and water drilling had pushed the lake to its limits. Local farmers have, for decades, drilled the land to provide irrigation water for farms and livestock. Now, the drilling is sapping the lake bed. A period of drought had, as of late January, left the lake in such a state that local officials were claiming the lake would be dead after another half-meter fall. The lake which is nourished both by springs and ground water has been deprived of flows both by human climate change induced drought and by human drilling into the lake’s spring-bed.
In Australia, drought conditions are now worse for some locations than at any time since 2003, a tall order since the 2003 to 2009 drought was Australia’s worst in 1,000 years. For Sydney, that means the lowest rainfall totals in more than 70 years. This particular drought hit both hard and fast with Australia seeing normal conditions before Christmas, but after, very intense heat and dryness resulted in a rapid scorching of farmlands, crops, and grazing fields. The dire drought situation has resulted in government relief funds being released to affected farmers. NSW Minister for Primary Industries, Katrina Hodgkinson noted to the Sydney Morning Herald:
“Seasonal conditions are now deteriorating at a rapid rate across a large portion of NSW and both the severity and speed at which this drought is moving is astonishing. Primary producers in some parts of NSW have simply not had the opportunity to prepare for another severe downturn in seasonal conditions so quickly after the Millennium drought broke.”
(A mostly full Lake Poyang as seen from Satellite on the left during May of 2012. A parched and almost completely dry lake Poyang as seen from Satellite during January of 2014. Image source: NASA/Lance-Modis.)
And, in China, the largest lake for that populous nation has now dried up. Poyang, a massive lake usually spanning 3,500 square miles has been turned into a sprawling field of earth parched and cracked by a combination of drought and water diversions resulting from the construction of the Three Gorges Dam. According to reports from The Guardian and Chinese News Sources, a drought stretching from 2012-2014 in the region of Poyang is now the worst in at least 60 years leaving lake refill almost non existent as upstream river flows to the lake were periodically cut off by water storage operations at the Three Gorges Dam. The result was an extreme lowering of lake levels and dry bed conditions that have driven farmers and fishermen in the region out of business.
Implications for world food security
Major droughts during 2011-2012 impacted many of the world’s primary agricultural basins, resulting in forward food supply dropping to as low as 72 days. Since that time, food supplies have slightly recovered but are well below previous levels last seen in the 1990s at 104 days. Food insecurity and failure to distribute food to the malnourished remains a priority at international agencies like the UN which has identified numerous countries including Cameroon, the Central African Republic, Somalia, Syria, Mali, Sudan and Nigeria, among others, as extreme risks for hunger and famine. Relief agencies have allocated billions of dollars to address this problem but the UN continues to identify climate change as a major threat to global food security with the potential to wipe out all previous progress moving forward.
The droughts in California, Turkey, Australia, China, Argentina and Brazil so far for 2014 put the world at risk for another bout of food insecurity later this year should major weather and climate related crop disruptions emerge in other primary food producers such as the bread baskets of the US, Russia, and Europe (The US, Brazil, China, Russia, and Europe are top food producers). It is worth noting that, in large part due to the ongoing southwestern drought, the US has revised a number of its crop projections downward for end 2014.
With polar amplification playing havoc with the Northern Hemisphere’s weather systems, with Australia sitting in a pool of expanding warm Pacific Ocean water that makes drought more likely there, and with the Eastern Pacific edging closer to La Nina, conditions warrant a continued monitoring of both weather and the state of world food supplies. The added global heat engine also impacts soils and crop growth in ways to which we are currently unaccustomed, resulting in more extreme instances of flash drought as well as flash flood. In this respect, the examples of Australia and Argentina are of particular concern.
Though global crisis has not yet returned, it lurks at the edges as drought, extreme weather and over-use of ground water supplies continues to threaten a wide swath of productive zones. So, at this point, the situation is one best described as tenuous with ongoing regional impacts over the Sahel region of Africa and in other sporadically vulnerable locales.