Storms, floods and climate change

Inevitably when there are large scale storms and floods the issue of climate change comes up. It’s difficult to attribute single weather events to large scale long term changes, but it’s easy to see an association.

If there is more heat in the oceans and if there is more heat in the atmosphere then storms are more likely, and more of them will be bigger.

There has been a lot of news coverage of hurricane Harvey in the US and the very heavy rains and widespread flooding in Texas. President Trump has said  ‘Nobody’s seen anything like this’ – he is prone to exaggerating but he could be right:

WP: Catastrophic flooding ‘beyond anything experienced’ in Houston and ‘expected to worsen’

“Catastrophic flooding in the Houston metropolitan area is expected to worsen,” the National Weather Service said Sunday. It added: “This event is unprecedented and all impacts are unknown and beyond anything experienced.”

But Texas isn’t the only place there have been floods recently.

FloodsGlobalWarming

South Asia floods: Mumbai building collapses as monsoon rains wreak havoc

Flooding across India, Nepal and Bangladesh leaves parts of cities underwater as storm moves on to Pakistan

Across the region more than 1,200 people are feared to have died and 40 million are estimated to have been affected by flooding in India, Nepal and Bangladesh.

Vast swaths of land are underwater in the eastern part of the Indian state of Uttar Pradesh, where more than 100 people have reportedly died, 3,097 villages are submerged and almost 3 million villagers have been affected by flooding, according to officials. Army personnel have joined rescuers to evacuate people from the area.

The storm reached Pakistan on Thursday, lashing the port city of Karachi, where at least 14 people have died, and streets have been submerged by water.

Sierra Leone mudslide and flood leaves more than 1,000 people dead

More than 1,000 people have died from the mudslide and flood that hit Sierra Leone’s capital nearly two weeks ago, a local leader and a minister have said during services honouring the disaster’s victims.

Thousands of people living in areas at risk during heavy rains have been evacuated.

Niger Reports 44 People Killed in Floods

At least 44 people have been killed in floods caused by torrential rains this season in Niger.

No single storm or flood can be directly linked to climate change, but an increasing number of increasingly severe floods could.

HOW CLIMATE CHANGE CONTRIBUTED TO MASSIVE FLOODS IN SOUTH ASIA

Heavy monsoon rains have caused disastrous floods and left millions displaced in South Asia. Like Harvey, climate change likely played a role.

“This is not normal,” Reaz Ahmed, the director-general of Bangladesh’s Department of Disaster Management, told CNN. “Floods this year were bigger and more intense than the previous years.”

Climate change appears to be intensifying the region’s monsoon rains. Rising sea surface temperatures in South Asia, for example, led to more moisture in the atmosphere, providing this year’s monsoon with its ammunition for torrential rainfall—much the same way abnormally high water temperatures in the Gulf of Mexico intensified Harvey before it stalled over Texas.

Warmer air temperatures in high latitude regions of the globe have also increased glacier melt, which has, in turn, raised the Himalayan rivers’ water levels and heightened the risk of flooding.

Heavy Flooding and Global Warming: Is There a Connection?

Climate change increases the probability of some types of weather. Recent heavy rains and flooding in the Northeast, Midwest, and Great Plains are consistent with a warming planet, and such events are expected to become more common over time.

As average temperatures in regions across the country have gone up, more rain has fallen during the heaviest downpours. Very heavy precipitation events, defined as the heaviest one percent, now drop 67 percent more precipitation in the Northeast, 31 percent more in the Midwest and 15 percent more in the Great Plains, including the Dakotas, than they did 50 years ago.

This happens because warmer air holds more moisture.

Two things are inevitable, rain and climate debate.

Leave a comment

7 Comments

  1. Alan Wilkinson

     /  September 1, 2017

    The counter evidence here: http://www.drroyspencer.com/

    Reply
  2. Maggy Wassilieff

     /  September 1, 2017

    Each year Bangladesh floods…. sometimes 20% of the country is underwater, sometimes 80% of the country.

    This is weather… natural
    https://en.wikipedia.org/wiki/Floods_in_Bangladesh

    Reply
    • Joe Bloggs

       /  September 1, 2017

      Flooding may be natural in Bangladesh (both from being a low lying country and from the lack of investment in infrastructure by successive governments) but the severity of current flooding is greater than in past years. Harvey is being described as a 1-in-1000 year event.

      These may be ‘natural’ events but their severity is unusual.

      Incidentally, I’ve been struck by how Western media have focused on Harvey and the 20-something deaths in Houston, while largely ignoring the 1,200+ deaths in Pakistan, India, and Bangladesh. Yet another indictment of Western/White privilege.

      Reply
  1. Storms, floods and climate change — Your NZ – NZ Conservative Coalition

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s