The 2013 Atlantic hurricane season, which officially ended on November 30th, will be noted in the record books as having been a relatively quiet year with the fewest hurricanes since 1982. In fact, it will be ranked as the sixth least-active Atlantic hurricane season since 1950. Despite this, the 2013 season was quite an active […]
In a recent article accepted for publication in the Journal of Climate, scientists in PhOD, S.-K. Lee (CIMAS) and C. Wang collaborated with R. Mechoso and D. Neelin, both at UCLA, to explore why the southern subtropical anticyclones are notably stronger in the austral winter than in summer, which is in contrast with the Northern Hemisphere (NH) in which subtropical anticyclones are more intense in summer according to the monsoon heating paradigm. They performed model experiments to show that during the boreal summer enhanced tropical convection activity in the NH plays important roles in strengthening the southern subtropical anticyclones.
While tropical cyclones can dramatically impact coral reefs, a recent study reveals their passage also exacerbates ocean acidification, rendering reef structures even more vulnerable to damage. Calcifying marine organisms such as corals that thrive in alkaline-rich waters are increasingly imperiled as seawater becomes more acidic due to the ocean’s uptake of carbon dioxide. The detrimental effects upon these organisms have been documented, but less is known about how reefs might react to ocean acidification when coupled with an additional stress factor such as a tropical cyclone.
NOAA hurricane scientists are expanding their observations this summer, working with NASA’s Hurricane and Severe Storm Sentinel (HS3) mission and its innovative Global Hawk unmanned aerial vehicles to push the boundaries of hurricane operations. NASA looked to NOAA’s hurricane experts to augment its HS3 science team, supporting their five-year mission to investigate the processes that underlie hurricane formation and intensity change in the Atlantic Ocean basin.
In a recent study by scientists at Boston University, PHOD, and NCAR, a new mechanism was uncovered for initiating ENSO events wherein SLP-generated North Pacific trade winds induce subsurface heat content changes that serve as precursors to El Ninos. This trade-wind charging mechanism of the equatorial Pacific is fundamentally different from any previously diagnosed, and studies examining the surface and subsurface ocean dynamics associated with this mechanism are underway.
Scientists at PHOD developed a synthetic method, which combines high-density expendable bathythermograph (XBT) temperature data along the AX08 XBT transect (which runs between Cape Town and NYC) with altimetric sea level anomalies, to estimate the variability of the off-equatorial currents, such as the North Equatorial Countercurrent and the North Equatorial Undercurrent, on seasonal to interannual timescales. Understanding how the ocean dynamics is liked to anomalies of temperature and wind-stress in the tropical Atlantic is critical to understand the climate and weather variability in the adjacent continental areas.
In its 2013 Atlantic hurricane season outlook issued today, NOAA’s Climate Prediction Center is forecasting an active or extremely active season this year.For the six-month hurricane season, which begins June 1, NOAA’s Atlantic Hurricane Season Outlook says there is a 70 percent likelihood of 13 to 20 named storms (winds of 39 mph or higher), of which 7 to 11 could become hurricanes (winds of 74 mph or higher), including 3 to 6 major hurricanes (Category 3, 4 or 5; winds of 111 mph or higher).
Using over 30 years of observations from drogued, satellite-tracked surface drifting buoys, Lumpkin and Johnson (2013) developed a methodology to map seasonally-varying surface currents at 1/2 degree resolution. Results from this study can be used to better understand how the ocean transports properties like heat, salt, and passive tracers, and serves as a reference to study changes in ocean currents over time. One key result from this study is the global distribution of mean, seasonal and eddy kinetic energy, which totals 4.6x1017J in the upper 30 m of the ocean and reveals the presence of three large eddy “deserts”, one in the Atlantic Ocean and the other two in the Pacific.
AOML partnered with NOAA’s Southeast Fisheries Science Center (SEFSC) to host an open house for local students and the public on May 24th and 25th. The two-day event drew 425 students and 275 members of the public for a total of 700 visitors. Staff from Representative Ileana Ros-Lehtinen’s office (FL-27) and Senator Marco Rubio’s (FL) office also participated in the very successful event.
Using over 30 years of observations from satellite-tracked surface drifting buoys, NOAA oceanographers derived a global climatology of seasonally-varying ocean surface currents at one-half degree resolution. This data set can be used to better understand how the ocean transports properties like heat, salt, and passive tracers, and as a reference to study changes in ocean […]