NOAA Teacher at Sea
Hayden Roberts
Aboard NOAA Oregon II
July 8-19, 2019
Mission: Leg III of SEAMAP Summer Groundfish Survey
Geographic Area of Cruise: Gulf of Mexico
Date: July 8, 2019
Weather Data from the Bridge
Latitude: 30.35° N
Longitude: 88.6° W
Wave Height: 1-2 feet
Wind Speed: 10 knots
Wind Direction: Northwest
Visibility: 10 nm
Air Temperature: 33°C
Barometric Pressure: 1012 mb
Sky: Few clouds
Science Log
Day one of my trip and we are delayed leaving. Growing up in Oklahoma, you think you know weather until one of the NOAA fishery biologists assigned to the ship provides you a lengthy explanation about the challenges of weather on setting sail. As he put it, the jet stream is throwing off the weather. This is true. Studies have suggested that for a few years the polar jet stream has been fluctuating more than normal as it passes over parts of the Northern Hemisphere. The jet stream is like a river of wind that circles the Northern Hemisphere continuously. That river meanders north and south along the way. When those meanders occur over the Atlantic and the Pacific Oceans, it can alter pressure systems and wind patterns at lower latitudes and that affects how warm or raining it is across North America and Europe.
This spring in Oklahoma, it has led to record-breaking rains that have flooded low lying areas across the Great Plains and parts of the southeastern United States. Thunderstorms have generally been concentrated in the southern and middle section of the US as the jet stream dips down. The NOAA biologist also indicated that the delay in our departure could be blamed on the El Niño effect.
El Niño is a natural climate pattern where sea water in the central and eastern tropical Pacific Ocean is warmer than average. This leads to greater precipitation originating from the ocean. According to NOAA scientists, El Niño is calculated by averaging the sea-surface temperature each month, then averaging it with the previous and following months. That number is compared to average temperatures for the same three-month period between 1986 and 2015, called the Oceanic Niño index. When the index hits 0.5 degrees Celsius warmer or more, such as right now, it’s classified as an El Niño. When it’s 0.5 degrees Celsius cooler or more, it’s a La Niña. During an El Niño, the southern part of the U.S. typically experiences wetter than average conditions, while the northern part is less stormy and milder than usual. During a La Niña, it flips, with colder and stormier conditions to the north and warmer, less stormy conditions across the south. However, the El Niño this year has been classified as weak, which means typically the wetter conditions do not push into the Gulf of Mexico region, but exceptions can occur. With the fluctuating jet stream, the El Nino has vacillated between the Plains region and the upper South and regions closer to the Gulf. Thus, the storm causing our delayed departure comes from a weather condition that has been pushed further south by the jet stream.
While these may be causes for the delayed departure, the actual sailing conditions at the time of our voyage are the main concerns. Looking at the NOAA Marine Forecast webpage (https://www.nws.noaa.gov/om/marine/zone/off/offnt4mz.htm), the decision for our delay is based on a storm producing significant wave heights, which are the average height of the highest 1/3 of the waves. Individual waves may be more than twice the average wave heights. In addition, weak high pressure appears to dominate the western Gulf and will likely last mid-week. Fortunately, we are set sail into the eastern Gulf off the coast of Florida. We should be able to sail behind the storm as it moves west. We do have to watch the surface low forming along a trough over the northeast Gulf later in the week. The National Hurricane Center in Miami (which provided weather data in the Atlantic and the Gulf for NOAA) predicts that all of this will intensify through Friday (July 12) as it drifts westward. This will produce strong to near gale force winds and building seas for the north central Gulf. Hopefully by then we will be sailing south of it.
Did You Know?
The weather terms El Niño and La Niña can be translated from Spanish to English as boy and girl, respectively. El Niño originally applied to an annual weak warm ocean current that ran southwards along the coast of Peru and Ecuador around Christmas time before it was linked to a global phenomenon now referred to as El Niño–Southern Oscillation. La Niña is sometimes called El Viejo, anti-El Niño, or simply “a cold event.” El Niño events have been occurring for thousands of years with at least 26 occurring since 1900.
Personal Log
I boarded NOAA’s Oregon II yesterday when the ship was virtually empty. It was Sunday, and we were not set to leave until mid-afternoon the following day (and now Tuesday, July 9). Spending the night on the ship was more comfortable than I had expected. While the stateroom was cramped (I share it with one other crew member), the space is surprisingly efficient. I had plenty of space to store my gear. The bunkbed was more cozy than restricted.
My first day in Pascagoula, MS was spent learning about the town. Pascagoula is a port city with a historic shipyard. Pascagoula is home to the state’s largest employer, Ingalls Shipbuilding, the largest Chevron refinery in the world, and Signal International, an oil platform builder. Prior to World War II, the town was a small fishing community, but the population jumped with war-driven shipbuilding. The city’s population peak in the late 1970s, but today, there are less than 25,000 in the area. Pascagoula continues to be an industrial center surrounded by the growing tourism industry across the Gulf region to the east and west of the port. The population also declined when Naval Station Pascagoula was decommissioned in 2006. The old naval base is located on manmade strip of land called Singing River Island and is in the middle of the port. The port still maintains a large Coast Guard contingent as well as serving as the home portfor the NOAA Ships Gordon Gunter, Oregon II, and Pisces. The NOAA port is actually called the Gulf Marine Support Facility and is located a block from NOAA’s National Marine Fisheries Service Mississippi Laboratory.
