Monsoon At Dead Halt: Chances For Summer El Nino Jump to 70% as India Swelters

mon-prog

Current advance of the Indian Monsoon indicated by the green line vs typical historic advance indicated by the dashed red line. Image source: India Meteorological Department.

The Indian Monsoon arrived in Sri Lanka on June 2nd, 8 days late, with extreme force. Dumping excessive rainfall even for a typically powerful event, it forced 2,500 to flee and resulted in the loss of 22 souls. There it stalled, battening into a Bay of Bengal moisture flow that hasn’t budged since May 23rd.

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By today, June 5th, powerful storms should be dumping rain over a wide swath including the entire southern tip of India, almost all of the waters between Myanmar and the Tamil Nadu and Andhra Pradesh coasts, and over most of Bangladesh. But in the satellite shot only scattered storms are visible where powerful, wall-to-wall squalls should now cover an impressive swath.

By this time last year, more than a third of India was obscured by cloud. Today, the skies of this nation of 1.25 billion people are ominously clear. The steely-gray aerial tint of coal ash smog is the most impressive feature in an otherwise open expanse from the northwest deserts to the southeast coast. A massive zone showing only sparse hint or hope of rain.

Even Sri Lanka seems mostly cloud-free. The monsoon and, more importantly, the crop-essential rains it brings are walled out, pushed into the margins by El Nino and some of the hottest global temperatures on record.

India monsoon stalled

Blazingly clear skies laced with ominous coal ash over India during a time when monsoonal storms usually advance. Image source: LANCE-MODIS.

Forecasts indicate that some of the long-delayed rain could arrive to the coast by tomorrow through Sunday. Sparse comfort to sweltering interior sections that may not now see the cooling monsoon until after July 1st.

Unrelenting Heat Risks Late Switch to Violent Storms

In the north, the heat and drought just builds and builds. Jaipur recorded its highest temperature in 33 years on Thursday at a scorching 46.3 degrees Celsius (115.3 F). Meanwhile, New Delhi hit a new record high for the day of 45 C (113 F). Forecasts for New Delhi on Saturday and Sunday show the potential for even more extreme heat with temperatures projected to climb to 116 F. Over the coming ten days, the coolest is expected to be Friday of next week at 109 F.

The continued delay of monsoonal rain combines with record heat throughout northern and western sections of India to enhance risks of drought and loss to crops. Heatwave conditions have already reduced Lychee fruit crop yields by 40%. But an extended stalling of the monsoon and ongoing heat could result in increased damage.

Atmospheric thickening that comes with such extreme heat can also spur intense rain and hail events causing another kind of damage to crops. So a flash switch from heat to heavy storms like those seen earlier this week in Sri Lanka may not be so much of a boon as a terrible jolt to affected lands.

Moderate to Strong El Nino Ever More Likely

This year’s monsoonal delay and related extreme weather were likely amplified by a combination of record atmospheric heat due to human-caused greenhouse gas forcing and a growing and strengthening El Nino. In April, global atmospheric temperatures hit new record highs of +.91 C above 1880s values even as El Nino rapidly gained ground in the Pacific through May.

Multivariate ESNO Index values catapulted to +0.93 in May hitting the seventh highest values on record for the month and pushing the current El Nino into Moderate-Strong range for this time of year. During previous years, similar high values resulted in strong El Ninos on 3 of 5 occasions in the climate record. So historical indicators point toward a 60% chance of a strong event emerging by later this year.

From to NOAA’s El Nino Discussion Page:

The long anticipated breakthrough to El Niño conditions in 2014 is clearly under way, leading to the next question of how big it will get. Of the 10 nearest-ranked April-May values, five had clearly come up to this level over the previous three months. Among those five, four continued at El Niño levels through the rest of the year, while one (1993) dropped back to borderline neutral conditions by the end of the year. One (2002) ended up as a weak-to-moderate event, while the other three (1957, 1987, and 1997) are classified as strong El Niño events in the MEI sense. In other words, the simple-minded odds for El Niño remain at or above 80% through the remainder of 2014, and are consistent with previous discussions on this website. The odds for a strong El Niño are perhaps slightly higher than before, somewhere around 60%.

Meanwhile, the official NOAA forecast is more cautious, with model interpretations pointing to a higher likelihood for a moderate El Nino during 2014.

Consensus El Nino Forecast

El Nino probability graph. Image source: CPC.

Overall, chances for evolution to full-blown El Nino rose significantly with today’s forecast now showing a 70% chance for El Nino development by this summer and nearly an 85% chance for El Nino development by Fall-Winter.

Regardless of El Nino strength, such an event is likely to have broad-ranging global impacts in the context of human-caused warming.

India’s Heightening El Nino + Climate Change Threat to Crops

For India, history shows numerous cases of severe monsoonal disruption during strong, moderate, and, recently, even weak El Nino events. In addition, record high atmospheric temperatures enhance extreme drought and flood potentials by amping up the hydrological cycle and thus increasing the rate of both evaporation and precipitation. Storms, where they do occur tend to be both tall and abnormally powerful under current human-warming related stresses even as droughts tend to develop with higher velocity and to persist for longer periods.

It is possible, due to both changes to the hydrological cycle and to atmospheric circulation, that the Indian monsoon has become even more sensitive to the El Nino pattern under current human-caused warming. This year’s monsoonal delay with El Nino just emerging shows an almost instant response to the forcing coming from increased temperatures in the Equatorial Pacific. As such, conditions of heightening threat for crop damage throughout a land where 1.25 billion people rely on the annual rains is a critical issue.

nepac_anomaly_ophi0

(Extraordinary sea surface temperature anomalies in the Northeast Pacific including numerous pools of +2.25 to +4 C or higher departures are indicative of both a strengthening El Nino pattern and a general warming of Ocean surface waters through human greenhouse gas heat forcing. Image source: NOAA Environmental Modeling.)

Overall, the forecast remains for continued monsoonal delay and disruption, continued heatwaves and a likelihood for extreme rainfall and storms in the regions where the monsoon finally arrives. With El Nino conditions in place over the Pacific now, with atmospheric temperatures rising into record range, and with an official El Nino status likely to be declared by summer, this forecast is lent yet more certainty and urgency.

Links:

India Meteorological Department

LANCE-MODIS

NOAA’s El Nino Discussion Page

CPC

North India Reels Under Heatwave

Monsoon Delayed Across India, Deadly Flooding in Sri Lanka

Weather Underground Ten Day Forecast for New Delhi

(Hat Tip to Timothy Chase)

 

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Monsoon Disrupted By El Nino + Climate Change as India Suffers Deaths, Crop Losses from Extreme Heat.

May is the month when the massive rainstorm that is the Asian Monsoon begins to gather and advance. This year, as in many other years, the monsoon gradually formed along the coast of Myanmar early in the month. It sprang forward with gusto reaching the Bay of Bengal by last week.

And there it has stalled ever since.

On May 25-27, an outburst of moisture from this stalled monsoonal flow splashed over the coasts of India. But by the 29th and 30th, these coastal storms and even the ones gathering over the Bengali waters had all been snuffed out. The most prominent feature in the MODIS shot of India today isn’t the rainfall that should be now arriving along the southeast coast, but the thick and steely-gray pallor of coal-ash smog trapped under a persistent and oppressive dome of intense heat.

Monsoon Disrupted

(MODIS shot of India on May 30th. See the open stretch of blue water in the lower right frame? That’s the Bay of Bengal which borders coastal India. During a normal year at this time, that entire ocean zone should be filled with the storm clouds of a building monsoon that is already encroaching on coastal India. Today, there is nothing but a smattering of small and dispersed cloud through a mostly clear sky. Image source: LANCE-MODIS.)

Monsoon Described as Feeble

Official forecasts had already announced as of May 27th that the annual monsoon was likely to be delayed by at least a week for southeast regions of India. Meanwhile, expected monsoonal rainfall for western and northern sections of India for 2014 fell increasingly into doubt.

From The Times of India:

The monsoon is likely to be delayed by 10 days, according to scientists at the Indian Institute of Tropical Meteorology (IITM) here. The IITM’s third experimental real-time forecast says that a feeble monsoon will reach central India after June 20 as against the usual June 15. Last year, the monsoon had covered the entire country by June 15.

The annual monsoon is key to India’s agriculture. The substantial rains nurture crops even as they tamp down a powerful heating that typically builds throughout the sub-continent into early summer. Without these rains, both heat and drought tend to run rampant, bringing down crop yields and resulting in severe human losses due to excessive heat.

But, this year, heat and drought are already at extreme levels.

Major Heatwave Already Results in Loss of Life for 2014

As early as late March, the heatwave began to build over the Indian subcontinent. The heat surged throughout the state, setting off fires, resulting in a growing list of heat casualties, shutting down the power grid and spurring unrest. Meanwhile, impacts to India’s agriculture were already growing as the Lychee fruit crop was reported to have suffered a 40% loss.

By late May, temperatures across a broad region had surged above 105 degrees shattering records as the oppressive and deadly heat continued to tighten its grip.

In a country surrounded on three sides by oceans, it is a combination of heat, humidity and persistently high night-time temperatures that can be a killer. Wet bulb temperatures surge into a high-risk range for human mortality during the day even as night-time provides little respite for already stressed human bodies. Such extreme and long-duration heat doesn’t come without a sad toll. As of today, early reports indicated a loss of more than 56 lives due to heat stroke (In 2012 and 2013, total Indian heat deaths were near 1,000 each year). That said, final figures on heat losses are still pending awaiting complete reports from all of India’s provinces.

“Climatologically, we know that heatwaves are increasing in frequency and the number of days exceeding 45ºC temperatures is increasing. The frequency will increase further with global warming, hence this is a good example of a situation where science and disaster management can come together and avert damage,” a spokesman for India’s National Disaster Management Authority noted on Friday.

Hot Dust

(Hot Dust. A dust storm rolls through New Delhi on Friday amidst furnace-like 113 degree heat snarling traffic and resulting in the tragic loss of 9 more lives. Image source: Gaurav Karoliwal/YouTube Screenshot.)

Today the heatwave continued to gain ground, with Kota and Rajasthan reaching an all-time record of 116 degree F (46.5 C) as New Delhi’s mercury hit 113 degrees F in the midst of a drought-induced dust storm. Dust shrouding the city spurred traffic chaos and in the heat, darkness, and confusion nine more souls were lost.

After two months of growing disruption due to heat and drought, the lands and peoples of India cry out for a Monsoon that is running later and later with each new weather report.

Climate Change + El Nino: Adding Heat and Beating Back the Monsoon

As systems approach tipping points, they are more likely to tilt toward the extremes.

For India this year, its seasonally warmest period from April to May found severe heat amplification from a number of global factors. First, climate change seeded the ground for the current Indian heatwave by adding general heat and evaporation to already hot conditions. With global average heating of +0.8 C above 1880s levels amplifying in the hot zones, early moisture loss due to higher-than-normal temperatures produces a kind of snowball effect for still more warming. Essentially, the cooling effect of water evaporation is baked out early allowing for heat to hit harder just as typical seasonal maximums are reached.

Equatorial Pacific Ocean Temperatures May 30

(Equatorial Pacific Ocean temperatures warmed to +0.63 C positive anomaly on May 30th, extending further into El Nino Range. Image source: University of Maine.)

In addition, this year saw rapid progress toward an El Nino event in the Pacific Ocean with sea surface temperatures warming into the El Nino range by mid-May and continuing to ramp higher. By today, Equatorial Pacific anomalies had hit +0.63 C according to GFS analysis, extending a run into El Nino conditions.

El Nino events typically allow for the formation of hot, drier air over India. These air masses tend to engender extreme heatwaves like the one we are seeing now even as they delay the onset of cooling monsoonal rains. In essence, the monsoon is confronted with a heavy and entrenched wall of hot air that doggedly resists being shoved aside. And this is the very situation we observe now over India — a sputtering monsoon to the east getting bullied by a brutally hot and thick air mass that just won’t give ground. Climate change only exaggerates the problem by increasing the intensity and inertia of the hot air mass.

Major monsoonal disruptions typically occur during years following an El Nino’s peak heating impact. For example, in 1998, during a period following an extreme El Nino, India suffered one of its most severe droughts and monsoonal delays on record. But during recent years preceding El Nino, such as 2009, India also saw severe heat, drying, and crop damage due to a weakening of the annual summer rains. So an early monsoonal enfeeblement and coincident strong heatwaves and droughts over India with El Nino still forming is cause for some concern and bears further monitoring.

Currently, temperatures over India are surging to between 5 and 12 degrees Celsius above already hot averages. With heat and drought firmly in place, forecasts are calling for a 1 to 2 week delay in the cooling and moisture-bringing monsoon as India continues to swelter.

Links:

Heatwave Persists Across India

LANCE-MODIS

Northern India to Endure Scorching Heat and Drought due to Weak Monsoon

Heatwave Continues in Raj, Kota

Lychee Crop Suffers 40% Loss Due to Heatwave

Dust Storm Blamed for 9 Deaths, Transportation Nightmare

Indian Monsoon Delayed as Heatwave Continues

Ten Day Delay in Monsoon

El Nino Delays Rain, May Spell Trouble for Government

El Nino May Disrupt Monsoon

(Hat Tip to Colorado Bob RE Tipping Points)

(Hat Tip to Mark from New England for Excellent Clarifying Questions)

 

 

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