Saturday August 18th… Dear Diary. The main purpose of this ongoing post will be to track United States extreme or record temperatures related to climate change. Any reports I see of ETs will be listed below the main topic of the day. I’ll refer to extreme or record temperatures as ETs (not extraterrestrials)😊. Here is today’s main climate change related topic:
Arctic sea ice and glaciers first come to mind when tipping points come up in climate conversations. Others we don’t initially think of are just as important in association with climate change such as the Indian monsoon. Did you know that changes with the Indian monsoon itself might be a tipping point? The Indian monsoon, which is the most prominent of the world’s monsoon systems, primarily affects India and its surrounding bodies of water blowing from the northeast during cooler months, reversing direction to blow from the southwest during a years warmest months.
As the globe warms weather patterns in association with predominate and seasonal wind flow will change due to carbon pollution. Looking at the chart below we see that the Indian monsoon will be affected greatly at +3C to +5C above preindustrial conditions. The entire Asian subcontinent with over one billion people depends upon the monsoon for water and a weather change, cooling temperatures down after heat has built during the spring. Already at about +1C we have seen horrible record heat over India and Pakistan the last few years before the monsoon sets up. Also, when the monsoon comes along we have gotten reports of tremendous record flooding rains from the subcontinent area. As we know a warmer world produces heavier downpours. What will probably happen to this part of the world, which is so rich in culture but where rampant poverty has existed for many decades?
For reference here is that global tipping point chart by Dr. Steffen indicating roughly at what global average temperature above preindustrial conditions cooling factors helping to regulate the climate become warming, thus spiking surface temperatures higher even if CO2 pollution ceased:
Global map by Will Steffen of potential tipping cascades. The individual tipping elements are color- coded according to estimated thresholds in global average surface temperature (tipping points) (12, 34). Arrows show the potential interactions among the tipping elements based on expert elicitation that could generate cascades. Note that, although the risk for tipping (loss of) the East Antarctic Ice Sheet is proposed at >5 °C, some marine-based sectors in East Antarctica may be vulnerable at lower temperatures.) From: http://www.pnas.org/content/early/2018/08/07/1810141115#ref-12
For today’s post I’ll refer to this Climate Citizen article:
Quoting from this article:
A new predictive study for future monsoon failure in India says that full season failure will become much more likely in the next two hundred years. Failure of the Indian Seasonal Monsoon (ISM) has been identified as a climate change tipping point by climate scientists.
The study highlighted that monsoon rains could fail about one year in every five between 2150 and 2200 with continued global warming due to continued human burning of fossil fuels, and related shifts in tropical air flows.
More than a billion people are dependent on the reliability of the Indian summer monsoon (ISM) for agricultural productivity. A small variability in rainfall on the Indian sub-continent has large impacts on agriculture. Lower rainfall can reduce crop yield, while excessive rain causes flooding damaging to crops and disruption to peoples’ lives. India’s monsoon lasts from June to September each year.
“Monsoon rainfall is vital for thousands and thousands of farmers in India and thus for feeding the people in the world’s second-most populous country,” lead author Jacob Schewe said. “So possible changes of precipitation patterns can have important implications for long-term adaptation planning of the Indian economy.”
Full monsoon failure in a season is possible but unlikely in present climatic conditions, but abrupt and strong shifts have ocurred in both the Indian and the East Asian monsoon during the last two glacial cycles and the Holocene, reports the study.
The study authors defined monsoon failure as a fall in rainfall of between 40 and 70 percent below normal levels. Monsoon rainfall has been relatively stable since accurate records started to be kept in 1870, but with a trend for more extreme rain events. There are signs that Cyclone intensity in the Northern Indian Ocean is increasing causing more damage to crops and infrastructure and lives, such as Cyclone Thane which hit the sub-continent in late December 2011.
“In this study, we show that more severe failure of ISM rainfall than ever observed in the past century is possible but unlikely under present climatic conditions, according to a realistic coupled climate model; and that such failure is projected to become much more frequent over the next 200 years under a climate change scenario.” says the study.
Here is the forecast chart from the prior article depicting the failure of the ISM (Indian Seasonal Monsoon) later this century:
Here is more information from Dr. Mann:
To summarize if the Indian monsoon fails intensely hot late spring temperatures will continue to build killing crops and straining fresh water supplies, jeopardizing the already impoverished lives of millions. The climate could “tip” such that intense heat normally modified by the monsoon would warm surrounding areas of the planet regardless of carbon pollution controls. After millions have perished due to the monsoon’s failure any survivors in the subcontinent area would have to adapt to a much drier, hotter region of southern Asia if we see global average temperatures get above +3C. It’s no wonder that the Paris Accords recommend that we keep global temperatures below +2C. This Indian monsoon factor should be on the conscience of all.
I’m getting strong indications that a record cool airmass will moe southward through the Plains and Midwest this coming week. We can see this early taste of fall initially affecting the Inter-Mountain West and western High Plains areas with some potential record low maxes on Sunday:
California will continue to bake. By Tuesday morning we can see the cool air spreading south and east through the Plains and Midwest as denoted by the blue coolers on this 850 millibar anomaly chart:
This is the Extreme Temperature Diary, so in an impartial manner I do report both record lows and highs. This time around we’ll see how many points the “cold team” will rack up on that “Record Scoreboard” this week.
(As usual, this will be a fluid post in which more information gets added during the day as it crosses my radar, crediting all who have put it on-line.)
(If you like these posts and my work please contribute via the PayPal widget, which has recently been added to this site. Thanks in advance for any support.)
The Climate Guy