Dead zone in Gulf of Mexico smaller this year than expected


hypoxia
The dead zone in the Gulf of Mexico was measured at nearly half its expected size this summer (NOAA)

Katelyn Weisbrod | August 9, 2018

Scientists found the dead zone in the Gulf of Mexico is smaller this year than in years past.

The zone of water lacking sufficient oxygen to support aquatic life at the end of the Mississippi River measured just over 2,700 square miles — about the size of the state of Delaware and the fourth-smallest the zone has been measured since 1985.

Experts at the National Oceanic and Atmospheric Association expected the dead zone to be more than double this size this year. The lack of oxygen in the water is caused in part by algal blooms stimulated by nutrient runoff from farm fields in states like Iowa into the Mississippi River. Algae deplete dissolved oxygen in the water making survival nearly impossible for fish and other aquatic life.

A possible explanation given by Dr. Nancy Rabalais of Louisiana State University is that winds in the area may have mixed oxygenated water with the water lacking oxygen, reducing the zone’s size.

Scientists from Louisiana State University measure the zone’s reach annually, but the size can vary significantly throughout the year. In 2017, the zone was measured at its largest size ever recorded — over 8,700 square miles. These data help inform efforts like the Iowa Nutrient Reduction Strategy about the progress of such initiatives to keep agricultural runoff and other nutrient loads from entering the Mississippi River.

Hawaii’s sunscreen ban


5565696408_8819b64a61_z.jpg
Coral reefs provide food and shelter to numerous marine animals. (flickr/USFWS)

Eden DeWald | July 11th, 2018

Hawaii is making a move to protect its coral reefs. A bill banning the distribution or sale of synthetic sunscreens in Hawaii was signed by Governor David Ige earlier this month. The ban will go into affect in January of 2021, and will prevent the sale of sunscreens that contain oxybenzone and octinoxate.

There are two main types of sunscreen found in any drugstore—chemical and physical. Physical sunscreen, or mineral sunscreen, often has active ingredients such as titanium and zinc oxide, which reflect or scatter UV rays by forming a protective layer on the skin. Synthetic sunscreens, which often contain oxybenzone and octinoxate, soak into the skin. They protect the wearer by changing the electromagnetic affect of UV rays. Physical sunscreens are not at all affected by the ban and will still be available for retail sale and distribution.

According to a 2015 study, oxybenzone has been found to cause the bleaching of coral reefs, as well as endocrine damage. There have been fewer studies done concerning octinoxate, but similar damaging effects have been associated with this chemical. Approximately 14,000 gallons are estimated to end up in the waters off the coast of Hawaii each year, consequently banning sunscreens with oxybenzone and octinoxate has the potential to remove thousands gallons of coral reef damaging chemicals from the environment each year.

Seattle bans straws


Straws
Five hundred million straws are used everyday in the US (Jeff G/flickr)

Eden DeWald | July 4th, 2018

Seattle is making a move to reduce single use plastics, by banning straws and any single use plastic utensils from restaurants and all other dining venues. Straws that are reusable or can be composted are still allowed, but the ordinance has a strong preference towards not providing any straws.  

Five hundred million plastic straws are used everyday in the United States. Because they are so lightweight, used straws find their way into the ocean quite easily. Once in the ocean, straws wreak havoc on marine life and seabirds. Approximately 70 percent of seabirds and around one third of turtles found have ingested, or gotten some kind of plastic superficially stuck on their body. There are around fourteen cities in the US that currently have straw bans, but Seattle is the largest city so far to place a ban on straws. However, New York City and the state of California have also gained momentum towards banning single use plastic utensils. 

The city of Seattle has made many other steps towards their mitigating impact on the surrounding ecosystem, including its efforts to help the salmon population. The Salmon in the Schools program allowed schoolchildren to hatch salmon and release them into, providing important environmental education to school children as well as helping to bolster the salmon populations numbers. 

 

Increase in nitrate pollution from Iowa


3931836528_ed31505eb8_z.jpg
The Mississippi River transports nitrogen to the Gulf of Mexico. (Ken L/flickr)

Eden DeWald | June 27, 2018

A new study from the University of Iowa finds that nitrogen pollution coming from Iowa has increased by close to 50 percent during the year of 2016 when compared to previous annual averages. The pollution from synthetic fertilizer made its way off of farms and into the greater water system. Twenty-three watersheds in Iowa were assessed, all of which drained either into the Mississippi or Missouri River, both of which eventually drain into the Gulf of Mexico.

Excess nitrogen in a water system spurs algae growth. After these algae blooms eventually decompose, bacteria or other small organisms feed on the dead algae and deplete oxygen within the water. This process is known as aquatic hypoxia, or eutrophication, and is responsible for the dead zone in the Gulf of Mexico. Iowa is not the only state that has problems with runoff, but with 72 percent of Iowa’s land being used for farming, Iowa is a major contributor to the eutrophication process.

The rise in nitrate pollution has occurred despite Iowa’s Nutrient Reduction Strategy, which just marked its five year anniversary earlier this year. The Nutrient Reduction Strategy is a voluntary program which involves 8,000 farmers and focuses on conservation methods such as cover crops and no-till techniques. Mike Naig, Iowa’s Secretary of Agriculture, wrote in a Des Moines Register article that he sees outreach and education about the effect that nitrates have on the water system as an essential aspect of improving Iowa’s water quality.

Coastal homes are threatened by sea level rise


28357572834_7c2ed02142_z
Beautiful sea front property is being threatened by sea level rise. (flickr/sdobie)

Eden DeWald | June 20th, 2018

Coastal homes all the way from Maine to Florida are feeling the threat of sea level rise. Approximately 300,000 homes along the East and West Coast of the United States are at risk for reoccurring flooding due to sea level rise. According to National Geographic, the global mean sea level has risen four to eight inches over the past century. However, the rate at which sea level is rising has been twice as fast for the last 20 years when compared to the first 80 years of the last century.

Sea level rise is caused by three main factors, all of which are consequences of climate change. Thermal expansion, the melting of ice over Antarctica and Greenland, and the melting of polar ice caps and glaciers, all contribute to the measurable rise that researchers have observed over the past century. In 2012, The Intergovernmental Panel on Climate Change predicted that sea level could rise up to 38 inches by 2100.

Sea level rise has serious consequences for homeowners. By 2045, the slowly creeping disaster of chronic flooding could pose great threats to coastal housing markets. The Union of Concerned Scientists conducted a study on the effect that sea level will have on the East Coast and the Gulf area. Kirsten Dahl, an author of the study, stated that the loss of tax revenue from affected homes could cut the tax base of small towns by as much as 70 percent. Coastal homes are highly sought after real estate, but buying a beach house may not be the luxury it once was.

 

Antarctica is melting, and its worse than we thought


371844144_c080cfc916_o
Antarctica has lost 3 trillion tons of ice since 1992, according to a new study. (Tak/flickr)

Katelyn Weisbrod | June 15, 2018

A new report found Antarctic ice is melting at an astoundingly higher rate than scientist thought.

The study published in Nature found that from 1992 to 2017, about 3 trillion tons of ice melted from Antarctica, increasing sea levels by about 7.6 millimeters around the world. Although it does not sound like much, a disproportionate amount of that rise was in the last five years. If sea level rise continues to accelerate, levels could be over three feet higher by 2100.

The Antarctic ice sheet, the study said, is an important indicator of global climate change. Rising sea levels is one of the main consequences of climate change, as it will increase flooding in coastal cities, especially during storms like hurricanes.

“This is the most authoritative and comprehensive treatment to date and should further reassure the public and policymakers that the science is solid, while perhaps making people more broadly less assured because the small warming and other climate changes to date have already triggered mass loss,” climate scientist Richard Alley of Penn State University told Axios in an email.

Major hydrologic shifts observed by NASA


5954768335_2291ba01fc_b
Researchers found that drier areas, like this drought-stricken field in Texas, are getting drier in a recent study. (U.S. Department of Agriculture/flickr)

Jenna Ladd | May 18, 2018

A recent study by NASA, the first of its kind, found that significant amounts of water are shifting around Earth’s surface.

Scientists used data from the Gravity Recovery and Climate Experiment (GRACE), two satellites, to track gravitational changes made by hydrologic shifts in 34 regions around the world. From 2002 through 2016, they paired this information with satellite precipitation data, NASA/U.S. Geological Survey Landsat imagery, irrigation maps, and public reports of human activities related to agriculture, mining and reservoir operations.

In short, researchers found that wetter areas are getting wetter and drier areas are getting drier. Jay Famiglietti of NASA’s Jet Propulsion Laboratory is one of the study’s authors. He explains, “We see a distinctive pattern of the wet land areas of the world getting wetter – those are the high latitudes and the tropics – and the dry areas in between getting dryer. Embedded within the dry areas we see multiple hotspots resulting from groundwater depletion.”

Scientists point to a couple of things to explain freshwater depletion in areas that are getting drier. In Saudi Arabia and many other parts of the world, for example, ground water has been depleted for agricultural purposes. The study also found that groundwater availability changes with periods of drought. From 2007 through 2015, southwestern California lost enough freshwater to fill 400,000 Olympic size swimming pools because the region saw less precipitation and snowpack during that time and had to rely on groundwater more heavily.

Freshwater loss in many regions was attributed to global warming that caused glaciers and ice sheets to melt away. However, Famiglietti said that much more research is needed to determine whether climate change caused the other hydrologic shifts.

GRACE Follow-On, GRACE’s successor, will continue to monitor the movement on water on Earth and is set to launch on May 22nd from Vandenberg Air Force Base California.