Illustration by Natalie Renier, © Woods Hole Oceanographic Institution
Warmer Ocean Waters Impacting More Than The Environment
This year’s Atlantic hurricane season got off to an early start in May, but even though there was a brief reprieve from tropical storms — thanks to a plume of Saharan dust earlier this month – we are once again seeing an increase in storm activity. In the past week, we have observed Hurricanes Douglas and Hanna, and Tropical Storm Gonzalo. And this week brings Tropical Storm Isaias, the earliest “I” storm on record, beating out Irene that formed August 7, 2005.
There are several contributing factors to the high tropical storm activity this year, including a mild winter, reduced wind shear and La Niña conditions, but the above-average sea surface temperatures are the constant factor that has impacted record-breaking storm activity over recent years. This trend is expected to increase faster than even some recent predictions. A new analysis found that the oceans are heating up 40 percent faster on average than estimated five years ago, breaking record temperature for several straight years.
There is well-documented evidence of how warmer sea temperatures affect sea life and the ocean environment, but the warmer ocean water also significantly affects industries. The accuracy of weather forecasting can impact efficiency and safety, especially in these challenging times.
Warmer waters create stronger hurricanes, which then act as giant heat engines, taking the energy from warm ocean waters and transferring that energy into the atmosphere. The warmer the sea surface temperature, the greater the tropical storm heat potential will be in a region. For coastal cities and businesses in the U.S., more storms making landfall means a higher risk for potential damage to ports, infrastructure, buildings, and livelihoods, as well as risk to health and safety. Flooding much farther inland is also a threat to businesses and agricultural supply chains.
Warmer sea surface temperatures also increase wave heights and wind speeds over ocean waters. A study published in Nature shows that over the last 30 years, observations note increases in average wave height and wind speeds, particularly in the Southern Ocean. Depending on the precise level of wind speed, this could lead to more opportunities for offshore power generation. Conversely, for land-based wind farms, warmer waters may mean weakened winds across the Northern hemisphere due to warmer Arctic waters creating a weaker polar vortexbetween the North Pole and equator. One study predicts that this may lead to as much as a 10 percent drop in wind across much of the Northern hemisphere by 2050, with a 14 to 18 percent drop by the end of the century. Accurate weather information helps to refine expected energy yield projections. Even small miscalculations can have long term effects on profitability, energy load and accessibility.
Warmer air and sea surface temperatures also means that the Northwest Passage could become an economically viable shipping route. Once considered impassable due to ice blocks throughout most of the year, the route is increasingly accessible and could cut considerable time at sea. The Arctic voyage opens up one of several routes that ships can take to traverse the Atlantic to Pacific Oceans. Weather forecasts created for seakeeping can help optimize routes and safety by factoring in marine conditions such as currents, wave height, ship build and cargo. These weather optimized routes can increase efficiency and reduce fuel usage by as much as 5 percent per voyage depending on the type of vessel, season and ocean.
As ocean temperatures rise, it continues to create secondary effects that impact the environment and the industries in ways that we are still discovering. All of this brings new challenges for forecasting and emphasizes the need for advanced weather models tailored for specific industry needs. As the meteorological community continues to research and model weather data based on evolving climate conditions, we can continue to help keep employees and operations safe, while helping industries prepared to respond and adapt to new weather trends and intensifying extreme weather.