India Ganges Floods 'Break Previous Records'

BBC News - Navin Singh Khadka

An aerial view of the flooded Ganges river in Allahabad city. AP

The monsoon floods in India's Ganges river this year have broken previous records, officials have told the BBC.
They said water levels reached unprecedented levels at four locations in northern India.
The highest record was in Patna, the state capital of Bihar where flood waters reached 50.52m (166ft) on 26 August, up from 50.27m in 1994.
Floods across India this year have killed more than 150 people and displaced thousands.

'Unprecedented'
"We have also recorded unprecedented flood levels at Hathidah and Bhagalpur of Bihar state and Balliya of Uttar Pradesh," chief of India's Central Water Commission GS Jha said.
"In all these four places, the floods crossed the previous highest flood level and they all were unprecedented."
Bihar is one of the worst flood-hit states in India with at least 150 deaths and nearly half a million people evacuated.
Neighbouring Uttar Pradesh has also been severely affected by floods in the Ganges.

The holy city of Varanasi has been submerged by the swollen Ganges. AP 

The Ganges has inundated large swathes of Uttar Pradesh state. AP

The third largest river in the world flows through these north Indian states meeting its tributaries before emptying into the Bay of Bengal.
The Indian Meteorological Department, however, has recorded deficient rainfall in these states past week and average rains since the monsoon started in June.

Breaking embankments
Some experts have blamed the silt the river carries for the floods. The Ganges is one of the highest sediment load carrying rivers.
The silt deposition is said to have raised the river's bed-level causing it to break embankments and flood the adjoining human settlements and farmlands.
Officials in Bihar have demanded that an artificial barrier in neighbouring West Bengal state bordering Bangladesh be dismantled to solve the silt problem.
They argue that the deposition of silt has obstructed several passages through the Farakka barrage.
As a result, they say, the Ganges' water flows back to Bihar and causes floods.
Silt deposition has also significantly raised the water level of Kosi river, one of the major tributaries of the Ganges.

The Ganges is flowing above the danger mark in Uttar Pradesh. AP

"The silt has so much accumulated in the river that we fear it might cause the water to damage the Kosi barrage and embankments," said Dev Narayan Yadav, a river expert pointing at the barrage built in the early 1960s.
"The silt has raised the river level higher to our villages' grounds, so you can imagine what risks we face."

Chronic problem
The BBC saw silt piling up and threatening to block many of the gates of the barrage on Kosi river, which is built and operated by India in Nepalese territory.
Some geologists say increased incidents of landslides in the Himalayan region have resulted in increased silt in the rivers flowing down to meet the Ganges.
"Since these are alluvial rivers carrying sediment loads, if we can control the silt then we will be able to manage the floods that have become chronic problems in the Ganges basin," said Mr Jha.

Bihar is one of the worst-affected states. AFP 

Floods across India have displaced thousands. AP

The Wadia Institute of Himalayan Geology in Uttarakhand state has also identified silting as the major flooding problem.
"Therefore de-silting of the rivers is the need of the hour and it needs to be done scientifically, from the middle of the rivers," said Professor Anil Kumar Gupta who heads the institute helping the government in geological issues.

Sand mining
Following uncontrolled sand mining from rivers across India for commercial purposes, India's Supreme Court in 2014 ordered a ban on extraction without a licence.
"Such sand mining was mainly done at riversides disturbing the flow of the rivers, therefore the silt will now have to be removed from the middle of the rivers."
India's central water resource authorities, however, believe construction of dams will deal with the problem effectively.
"Non-structural measures like moving people to safe areas have not been effective enough," says Mr Jha.

The silt deposition is said to have raised the river's bed-level causing it to break embankments. AP

The Ganges is the third largest river in the world. AP 

"The dams we plan to build will store flood waters to prevent flooding and they will also have the technology to take care of the silt."

He said the Central Water Commission aimed to build three major dams - two in upstream Nepal and one in Arunachal Pradesh.
"They have been planned for quite sometime and we are certain that we will be able to build them and solve the chronic problem of floods."

Links

• Is India facing its worst-ever water crisis?
• India climate: What do drowning rhinos and drought tell us?
• How monsoon rains lift India's spirit and economy

NASA: Earth is warming at a pace 'unprecedented in 1,000 years'

The Guardian - Oliver Milman

Records of temperature that go back far further than 1800s suggest warming of recent decades is out of step with any period over the past millennium

The sun sets beyond visitors to Liberty Memorial as the temperature hovers around 100F in Kansas City, Missouri, last month. Photograph: Charlie Riedel/AP

The planet is warming at a pace not experienced within the past 1,000 years, at least, making it "very unlikely" that the world will stay within a crucial temperature limit agreed by nations just last year, according to NASA's top climate scientist.
This year has already seen scorching heat around the world, with the average global temperature peaking at 1.38C above levels experienced in the 19th century, perilously close to the 1.5C limit agreed in the landmark Paris climate accord. July was the warmest month since modern record keeping began in 1880, with each month since October 2015 setting a new high mark for heat.
But NASA said that records of temperature that go back far further, taken via analysis of ice cores and sediments, suggest that the warming of recent decades is out of step with any period over the past millennium.

Proxy-based temperature reconstruction. Photograph: NASA Earth Observatory

"In the last 30 years we've really moved into exceptional territory," Gavin Schmidt, director of NASA's Goddard Institute for Space Studies, said. "It's unprecedented in 1,000 years. There's no period that has the trend seen in the 20th century in terms of the inclination (of temperatures)."
"Maintaining temperatures below the 1.5C guardrail requires significant and very rapid cuts in carbon dioxide emissions or co-ordinated geo-engineering. That is very unlikely. We are not even yet making emissions cuts commensurate with keeping warming below 2C."
Schmidt repeated his previous prediction that there is a 99% chance that 2016 will be the warmest year on record, with around 20% of the heat attributed to a strong El Niño climatic event. Last year is currently the warmest year on record, itself beating a landmark set in 2014.
"It's the long-term trend we have to worry about though and there's no evidence it's going away and lots of reasons to think it's here to stay," Schmidt said. "There's no pause or hiatus in temperature increase. People who think this is over are viewing the world through rose-tinted spectacles. This is a chronic problem for society for the next 100 years."
Schmidt is the highest-profile scientist to effectively write-off the 1.5C target, which was adopted at December's UN summit after heavy lobbying from island nations that risk being inundated by rising seas if temperatures exceed this level. Recent research found that just five more years of carbon dioxide emissions at current levels will virtually wipe out any chance of restraining temperatures to a 1.5C increase and avoid runaway climate change.

Temperature reconstructions by NASA, using work from its sister agency the National Oceanic and Atmospheric Administration, found that the global temperature typically rose by between 4-7C over a period of 5,000 years as the world moved out of ice ages. The temperature rise clocked up over the past century is around 10 times faster than this previous rate of warming.
The increasing pace of warming means that the world will heat up at a rate "at least" 20 times faster than the historical average over the coming 100 years, according to NASA. The comparison of recent temperatures to the paleoclimate isn't exact, as it matches modern record-keeping to proxies taken from ancient layers of glacier ice, ocean sediments and rock.
Scientists are able to gauge greenhouse gas levels stretching back more than 800,000 years but the certainty around the composition of previous climates is stronger within the past 1,000 years. While it's still difficult to compare a single year to another prior to the 19th century, a NASA reconstruction shows that the pace of temperature increase over recent decades outstrips anything that has occurred since the year 500.
Lingering carbon dioxide already emitted from power generation, transport and agriculture is already likely to raise sea levels by around three feet by the end of the century, and potentially by 70 feet in the centuries to come. Increasing temperatures will shrink the polar ice caps, make large areas of the Middle East and North Africa unbearable to live in and accelerate what's known as Earth's "sixth mass extinction" of animal species.

Links

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• Global sea levels have risen 8cm since 1992, NASA research shows
• NASA climate study warns of unprecedented North American drought
• NASA scientists observe Arctic sea ice changes – video
• NASA launches carbon-hunting satellite - video
• NASA turns to CloudSpotter app to create global 'cloud atlas'
• NASA scientist's study quantifies climate change link to extreme weather
• That snow outside is what global warming looks like