You don’t want to push the system past those kind of tipping points because, if we do, we leave a situation for our children and grandchildren that will be out of their control. They won’t be able to stop it.
This post is the second in the climate tipping points series. Part one is here. Before getting into some of the other tipping points, I want to mention an excellent new paper, Going to Extremes: Climate Change and the Increasing Risk of Weather Disasters, written by Dr. Jonathan Overpeck, Professor of Geosciences and Atmospheric Sciences at the University of Arizona. It encapsulates a lot of pertinent information explaining the new reality of extreme weather events which humans will have to contend with from here on out.
Scientists warn that global warming may threaten global food security as the changing climate could fundamentally affect humanity’s collective ability to feed itself. Although an increase in the amount of carbon dioxide in the atmosphere may initially promote plant growth, it does not necessarily translate into more food. Crops tend to grow more quickly in higher temperatures, leading to shorter growing periods and less time to produce grains. However, a changing climate will bring other, more significant hazards for agriculture, including greater water stress and the risk of higher temperature extremes that can quickly damage crops.
Agricultural impacts will vary across regions and by crop. Moderate warming and changes in precipitation are expected to decrease yield in seasonally dry and low-latitude areas. In California, where half the nation’s fruit and vegetable crops are grown, climate change is projected to decrease yields of almonds, walnuts, avocados, and table grapes by up to 40% by 2050.
Scientists have determined that any benefits increased carbon dioxide for some crops will be largely outweighed by negative factors if global temperature rises more than 1.8°F (1.0°C) from late 20th century values. It is expected that for each degree of warming, yields of corn in the United States and Africa, and wheat in India, will drop by 5-15%. In addition, if temperatures rise 9°F (5°C), most regions of the world would experience yield losses and global grain prices would potentially double…
…[The] NOAA recently concluded, after looking through 50 years of weather data, that droughts like the record 2011 Texas drought was made “roughly 20 times more likely” because of global warming. Indeed, observations have shown that certain extremes—high heat, heavy precipitation and floods, duration and intensity of droughts and extremes related to higher sea levels—have increased over the last half of the century.
Continuing on the list of Lenton’s and Schellnhuber’s tipping points…
6.) The Sahara and Sahel in Africa could change dramatically, becoming either far more dry or far more wet, as ocean temperature and vegetation-climate feedbacks change within a decade or so. This is considered an “intermediately sensitive” tipping point with large uncertainty.
Desertification and lower rainfalls with infrequent torrential floods from a warming climate is the clear winner according to studies:
One of the most significant climatic variations in the African Sahel since the late 1960s has been the persistent decline in rainfall. The Sahel is characterized by strong climatic variations and an irregular rainfall that ranges between 200mm and 600 mm with coefficients of variation ranging from 15 to 30% (Fox and Rockström, 2003; Kandji et al., 2006). A rainfall decrease of 29-49% has been observed in the 1968-1997 period compared to the 1931-1960 baseline period within the Sahel region (McCarthy et al., 2001). The West Africa region has experienced a marked decline in rainfall from 15 to 30% depending on the area (Niasse, 2005). The trend was abruptly interrupted by a return of adequate rainfall conditions in 1994. This was considered to be the wettest year of the past 30 years and was thought to perhaps indicate the end of the drought. Unfortunately, dry conditions returned after 1994 (McCarthy et al., 2001).
The rainfall variability in Africa has been studied by numerous authors since the beginning of the recent drought period in the 1970s. Many studies focused on the Sahelian areas ( Farmer, 1988; Lamb & Peppier, 1992; Hulme, 1992). Others also compared Sahelian rainfall with rainfall over other West African and Central Afrcan rregions (Thompson et al. 1985; Buishand, 1984).
(click on pic to go to original full story)…
Impacts of climate change
Eminent scientist, Sir Gordon Conway, the former chief scientific adviser to the British Department for International Development and the former President of the Rockefeller Foundation said that Africa is already warming up faster than the global average and that the continent will experience a greater amount of intense droughts, floods and storm surges as a result…
…While there are many facets to climate change in Africa, in the case of central Nigeria it is important to look at food, water and migration. The environmental concerns in the Delta region and rising water levels across the south coast present challenges in themselves and would require an article in themselves.
Climate change threatens the ability of West Africa to compete in the global food system. An increase in temperature will undoubtedly reduce yields in a region where the population is set to double within the next two decades. Some projections claim that crop production will drop by 50% within the same timeframe as this population boom.
Nigerian food producers do not have the capacity to deal with such climate or population fluctuations. Consequently food availability in many regions will be dangerously compromised leading to greater competition for resources.
In addition to the concerns of food production, the availability of water in the Sahel reached crisis levels several times in recent years. In 2010 the region suffered a widespread famine, partially as a result of water shortages, and is now in the midst of an ongoing drought that has affected 18 million people.
Debates continue to rage over the future of Sahelian water as some project a decrease in rainfall of 40 percent in a region beset by drought already. Others have posited that rainfall may increase the Sahel but that such a change would likely lead to an infestation of locusts the like of which have been destroying farmland in Mali and Niger in recent weeks. When the rains do arrive the cities in the region are often unable to deal with them, evidenced by yesterday’s lethal flooding in Jos which has killed at least 35 people.
While future projections of waterfall vary, there is no doubting the present and impending threats from desertification.
Desertification is the most egregious form the temperature increase has taken as much of the Sahel is already suffering from climate-induced drought. Approximately 1,350 square miles of Nigerian land turns to desert each year. To put it in perspective, that is over twice the size of Greater London becoming impossible to farm each year. This leads to both farmers and herdsmen having to abandon their homes to move to an area with more abundant resources.
Migration crisis and conflict
Encroaching deserts do not merely mean water scarcity and a threat to food security but also mass migration. The direct competition for resources has the potential to become more acute in several regions of Nigeria and beyond in West Africa.
An example would be the millions of Malians and Burkinabes in Cote d’Ivoire as a result of the Sahelian droughts of the 1970s and 1980s. When the use of migrant labour lost its appeal to Cote d’Ivoire amidst the conflicts of the 1990s it set the course for outside interests to have a major impact on internal conflicts. Migration disputes continue between the two countries to this day including a substantial impact upon the Ivorian crisis of 2010-11.
As the Sahel continues to dry up as a result of climate change, the land can no longer support the animal stocks required by herders to survive. Since the only useful land to the herders is to the south of the desert, they move their herds towards the agricultural regions populated by sedentary farmers. Naturally, the destruction of crops by the herds creates tensions between those moving the animals and those who struggle to grow enough food for themselves in an increasingly unforgiving climate.
The policy solutions up to this point have focused on short-term political factors leading to knee-jerk responses to the violence. Communities in Ghana, Burkina Faso and Nigeria have expelled Fulani herders. The existential threat is forcing the Fulani to fight back.
A refusal to acknowledge the role that climate change has played in the region has led to a failure of governance. Such forced relocations are merely postponing the problem for a future government rather than trying to fix it. In this sense the agricultural policies in Nigeria have become a microcosm for climate policy.
In the case of Nigeria poor governance as a result of political short-termism has exacerbated the food crisis, the catalyst for migration issues. Until the 1970s agriculture made up 60% of Nigeria’s GDP. Since then technological stagnation, myopic policies and corruption have turned the country into a net importer at a cost of $150 billion each year. The $500 million allocated to agriculture in the 2012 budget could be enough to facilitate the needs of the country if spent wisely. Some have even argued that Nigeria has the capacity to be the breadbasket for the whole of West Africa.
Politics of inaction
Political short-termism has blighted Plateau State both in terms of local politicians and the global response to climate change. The sudden explosions of conflict in the region have been predicted for decades. Despite the upsurge in brutal violence, the policies remain largely the same.
With roughly 40% of Africa now affected by desertification, solutions will have to come soon. One such solution is the ‘Green Wall’, a wall of trees 4,300 miles long and 9 miles wide stretching across the African continent from Senegal to Djibouti. The idea has been advocated by West African leaders for over 30 years but has only now been realised.
Erecting walls has rarely provided a long-term solution to conflict. It is unlikely to do so for climate change.
7.) The El Nino Southern Oscillation, occurring across the tropical Pacific Ocean roughly every five years, refers to patterns of warming and cooling in the Pacific Ocean that affect weather worldwide. It could within 100 years change to a persistent warm or cool pattern, or change so that warm El Nino patterns are more intense, leading to more intense droughts in some areas, and likelihood of flooding elsewhere. This is considered an “intermediately sensitive” tipping point with large uncertainty.
Kevin Trenberth, Senior Scientist in the Climate Analysis Section at the National Center for Atmospheric Research (NCAR), suggests that we are seeing changes in El Nino:
There’s another elephant in the room: the long-term influence of greenhouse gases. “In my view, El Niño and La Niña are very likely changing as a consequence of climate change, but such changes cannot be measured when you get only one event every three to seven years,” says Trenberth. “The natural variability is enough to make it impossible to determine a climate change signal.” Still, he adds, when it comes to El Niño and La Niña, it’s best not to assume that past performance is any guarantee of future results.
This year El Nino was pretty much nonexistent, turning into La Nada:
8.) The Atlantic thermohaline circulation (THC) is a global 3-dimensional belt of ocean currents that transports large amounts of heat and freshwater around the world. In the North Atlantic, it manifests in a meridional overturning circulation (AMOC) which, through its northward transport of warm tropical waters by the Gulf Stream and North Atlantic Current, ensures these warm waters reach Europe.
The THC could collapse within 100 years as warming of the oceans alters water density and disrupts the global circulation of the seas. This is considered a “lowly sensitive” tipping point, with intermediate uncertainty.
from ‘Abrupt Climate Change‘ (Lead Author: Thomas L. Delworth,* NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ):
…AMOC and the likelihood of future changes in the AMOC in response to increasing greenhouse gases, including the possibility of abrupt change.
We have five primary findings:
• It is very likely that the strength of the AMOC will decrease over the course of the 21st century in response to increasing greenhouse gases, with a best estimate decrease of 25-30%.
• Even with the projected moderate AMOC weakening, it is still very likely that on multidecadal to century time scales a warming trend will occur over most of the European region downstream of the North Atlantic Current in response to increasing greenhouse gases, as well as over North America.
• No current comprehensive climate model projects that the AMOC will abruptly weaken or collapse in the 21st century. We therefore conclude that such an event is very unlikely. Further, an abrupt collapse of the AMOC would require either a sensitivity of the AMOC to forcing that is far greater than current models suggest or a forcing that greatly exceeds even the most aggressive of current projections (such as extremely rapid melting of the Greenland ice sheet). However, we cannot completely exclude either possibility.
• We further conclude it is unlikely that the AMOC will collapse beyond the end of the 21st century because of global warming, although the possibility cannot be entirely excluded.
• Although our current understanding suggests it is very unlikely that the AMOC will collapse in the 21st century, the potential consequences of such an event could be severe. These would likely include sea level rise around the North Atlantic of up to 80 centimeters (in addition to what would be expected from broad-scale warming of the global ocean and changes in land-based ice sheets due to rising CO2), changes in atmospheric circulation conditions that influence hurricane activity, a southward shift of tropical rainfall belts with resulting agricultural impacts, and disruptions to marine ecosystems.
9.) The Indian summer monsoon, which is needed to sustain crops, could collapse anytime as land-to-ocean pressure gradients change with pollution and warming patterns. That could lead to an “erratic” fluctuation that would “chaotically change between an active and a weak phase.” This is considered an “intermediately sensitive” tipping point with large uncertainty.
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THE dizzying midday heat of India’s northern plains cracks the earth. Farmers slump on the charpoys on which they sleep outdoors. It should be raining, yet the sky is clear. Prithi Singh, lean and wrinkled, says his entire rice crop has withered, along with fields sown for fodder. After two summers of erratic and delayed monsoons, this year the rains simply failed…
The monsoon months, June to September, bring three-quarters of India’s annual rainfall. Official studies show it to be erratic in four out of every ten years. Yet farmers rarely get any useful warning of shortfalls. As recently as late June, India’s meteorologists were predicting a normal monsoon. Punjab and Haryana, two north-western agricultural states, now say rains are about 70% below average.
Six western states have issued drought warnings.
The government in Delhi says it may soon offer emergency help. The country remains predominantly rural: over 600m out of 1.24 billion Indians rely directly on farming. Nearly two-thirds of Indian fields are fed only by rain. A one-off drought is tolerable. Rural job-creation schemes have lifted incomes for the poorest. Food prices have only started to creep up. Granaries are overflowing, thanks to recent bumper crops.
What is disturbing, though, are tentative signs of long-term change to the summer rains. A less stable monsoon pattern would be harder to predict. It would arrive late more often, yield less water, become more sporadic, or dump rain in shorter, more destructive bursts (which happened two years ago in Pakistan, where the Indus basin disastrously flooded). The concerns of experts about the monsoon long predate today’s dry spell.
Too little is known about summer weather systems on the subcontinent. India is short of observation stations, weather planes, satellites, climate scientists and modellers. The government and foreign donors are scrambling to make amends. But even with better data, monsoons are ill-understood once they leave the sea or low-lying land. At altitude, notably, for instance, approaching the Himalayas, it is far trickier to grasp just how factors such as wind direction, air pressure, latent heating and moisture levels interact to deliver monsoon rains.
One trend looks clear: India has grown warmer over the past six decades. Glaciers are melting in the Himalayas, and orchards in the range’s valleys are being planted on ever-higher slopes in search of a temperate climate. Crops in the northern grain belt, notably wheat, are near their maximum tolerance to heat, and so are vulnerable to short-term blasts of higher temperatures. North India’s cities are also growing hotter.
How more warmth affects the monsoon is not straightforward. A land mass heating faster than the oceans will, in theory, draw in more moisture to produce heavier monsoons. Yet the reverse appears to be happening. Specialists who met in February in Pune, in Maharashtra state, reported a 4.5% decline in monsoon rain in the three decades to 2009.
India’s leading climate modeller, R. Krishnan, of the Indian Institute of Tropical Meteorology in Pune, points to a study showing a “steady decline” in rainfall on the Western Ghats, which run down the west coast. A Japanese model that he has applied to southern India predicts that a still more rapid decline in rainfall is likely.
Such a fall may matter little for states such as Kerala in the south, which gets a monthly drenching of 50 centimetres (20 inches) during the wet season. But Mr Krishnan notes other changes, notably evidence that far fewer depressions have formed in the Bay of Bengal, off India’s east coast, in recent summers. Since these help drive rain to India’s arid northern plains, he concludes that “there is every reason to be concerned about the monsoon.”…
…Yet a decline in average rainfall may not be the main worry. Experts who met in Delhi in May to discuss climate-induced “extreme events” in India suggest that likelier threats include more short and devastating downpours and storms, more frequent floods and droughts, longer consecutive dry days within monsoons, more rapid drying of the soil as the land heats, and a greater likelihood that plant and animal diseases might spread.
It does not bode well for farmers, or for crammed cities with poor sewerage and other rotten infrastructure. Slums and coastal cities look especially vulnerable. Mumbai was overwhelmed in 2005 when nearly a metre of rain was dumped on the city in 24 hours.
Such events will happen more often, the highest official in the country’s environment ministry warns. He wants urgently to bring about a big increase in insurance schemes that spread weather-related risks. Rajendra Pachauri, who leads the United Nations’ Intergovernmental Panel on Climate Change, worries that India is not yet even seriously debating the new threats. He says it is ill-prepared for floods and droughts “that are now considered once-in-every-20-years events, but will be happening once in two years.
Part three of climate tipping points will be posted in a week or two.
“Capitalism has the innate genius of being inexorably driven to destroy everything it encounters, in order to turn it into money. ‘Creative destruction’ -the creation of money through the destruction of life. It is reaching its absolutely inevitable apotheosis now.”
~ Mulga Mumblebrain
Capitalism has unleashed the real weapon of mass destruction…