Hoping for a mild, dry winter? You might be disappointed

El Niño gone/ La Niña here

Winter 2016-2017 is upon the Dayton region, and from the looks of things it’s likely to be very different winter than winter 2015-2016. A major reason for the change is the strong El Niño conditions which persisted throughout winter 2015-2016 are gone. La Niña conditions have taken their place. However, the current La Niña is weak, and its impact on local weather will probably not be as great as the 2015–2016 El Niño event.

La Niña winters tend to bring moisture to the Ohio Valley

La Niña conditions occur when equatorial sea surface temperatures are below average in the central and east-central Pacific Ocean. This is the exact opposite of what occurs during an El Niño. Like El Niño, La Niña impacts global weather patterns by influencing the position of the polar and Pacific jet streams. During La Niña winters, the polar jetstream tends to dive south over North America. The polar jet stream brings cold air and storm systems to northern portions of the United States.

la-nina-graphic

According to National Ocean and Atmospheric Administration, we can expect La Niña conditions to persist through February 2017. After February, its likely La Niña will transition to neutral conditions sometime during spring 2017. Neutral conditions mean that neither El Niño nor La Niña conditions are present in the equatorial Pacific Ocean.

So what does this mean for our region in terms of winter weather?

Winter 2016 – 2017 is likely to be wetter and cooler

The odds favor a wetter and cooler winter 2016 – 2017 compared to winter 2015 – 2016. Is this a guarantee? No it’s not. There are a multitude of other climatic factors at play in determining winter weather outcomes in our region. El Niño and La Niña events are just one of those factors.

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What’s ahead for our region’s weather?

By Mike Ekberg, Manager for Water Resources Monitoring and Analysis

In my August 1, blogpost, “Climate Change: Is It Real?” we noted that our climate is always changing. Some people want to debate the cause, but that’s not nearly as important as planning for the changes that are expected.

A warming trend will amplify the extremes in our region’s climate, according to the Third National Climate Assessment. We can expect more intense summer heat waves, more droughts, and more floods.

More rain when we don’t need it and less rain when we do
The Third National Climate Assessment says here’s what we can expect over the next 35 years:

  • Annual average temperature in our region is expected to increase as much as 4.9 degrees Fahrenheit.
  • Winter and spring precipitation is expected to increase 10-20 percent.
    • We’ll see less snow and more rain.
    • Storms are likely to be stronger, increasing the chance of flooding.
  • Summer rainfall is expected to drop 8 percent, increasing the chance of droughts.
    • Summer droughts can increase water demands on utilities for lawn irrigation.
    • More frequent summer droughts can increase water demand for crop irrigation.

The Miami Valley will need to cope with intense winter and spring rain events when human water demand is low. Likewise, we’ll need to cope with hotter – and sometimes drier – summers when human water demand is high.

Making changes now key to coping in the future
How can our region successfully cope with these challenges?

Planning and wise infrastructure investment is the key. Here are some steps communities in our region can take to prepare for a warmer future.

  • Minimize paved surfaces to reduce flash flooding and streambank erosion.
  • Encourage infiltration areas such as pervious pavement, rain gardens, and drainage swales to reduce urban runoff.
  • Install flood warning systems in areas prone to flash flooding.

    rain garden

    Rain gardens reduce storm water runoff by using the rain water on your property, allowing it to soak into the ground and recharge the aquifer.

  • Invest in more water storage to meet summer demands.
  • Manage summer water demand through regulations, rate structures, or consumer incentives.
  • Use the most efficient irrigation technologies to reduce summer water demand.
  • Provide cooling shelters for people who do not have access to air conditioning during summer heat waves.

The time to act is now
Taking steps now is the key to preparing for a changing world. Our region is fortunate to have sufficient water resources and should be able to weather the forecasted changes if we manage those resources well. If we don’t prepare now, we’ll be playing catch up later, and that could prove to be costly.

 

Climate Change: Is It Real?

By Mike Ekberg, Manager for Water Resources Monitoring and Analysis

Is climate change for real? Is the world getting warmer, or is all this talk about a warming climate just a bunch of hooey?

Let’s consider some recent findings. According to the National Oceanic and Atmospheric Administration (NOAA), June 2016 was the warmest June ever recorded in terms of average worldwide temperatures. In fact, June 2016 was the 14th consecutive month to set a new monthly global temperature record.

NOAA has been keeping track of monthly global temperatures for 137 years. It compares current monthly global temperatures with the 20th century. The average global temperature for June was 0.92°C (1.62°F) above the 20th century average.

Do you know when the last time June global temperatures were actually below average? In 1976 – 40 years ago!

NOAA also tracks key indicators worldwide of a changing climate. According to NOAA’s latest State of the Climate Report:

  • Land, air, and sea surface temperatures are rising.
  • Glaciers and ice sheets are melting and decreasing in size.
  • Sea level is rising.
  • Snow cover and the extent of sea ice are decreasing.
  • Ocean heat content is increasing.

All of these indicators point convincingly to a warming world.

Is it global warming? Is it climate change? Is it simply changing weather patterns? Call it what you want, but the fact is earth’s climate is dynamic and always redefining normal. A continental-sized glacier once covered the Dayton region. So there’s always been and likely always will be “climate change.”

The debate, if there is one, is over how much we humans are impacting the current warming trend. And the bigger questions we should all be asking are, “What challenges does a changing climate pose for us?” and “How are we going to meet those challenges?”

NOAA Climate change graphic 10 Indicators of a Warming World