Tag Archives: Kanata

How Did Water Get To Earth?

Water..covers &0% of the surface of the Earth, so important to life on Earth but where did it come from.

Scientists have come up with several ways water got to Earth, including it was always here or in dirty ice balls called comets. Asteroids are also on the list as originators of water. More than 4 billion yrs ago Asteroids pummeled the planet in great numbers in a period called the great bombardment.

Samples of asteroids  called carbonaceous chondrites, show they contained water. The heat of impact would be great with the resulting loss of water. Scientists at Brown University  and John Hopkins have shown through experiments on a smaller scale that the water could have been captured in Earth’s rock.

Using NASA’s vertical gun, a 3 story high apparatus designed to fire projectiles at a target at different angles, the scientists shot pea sized pebbles called antigorite at pumice. This mimics an asteroid hitting Earth , but on a small-scale. The gun shoots the pebbles about 10 ft, but at a speed of 11,000 miles an hour. At an impact angle of 45 degrees as much as 30% of the water was captured.

If this were to be the impact of a real asteroid the water could be later released as steam from lava flows and contribute to life on Earth.

The scientists recognize that this process would not account for all the water on Earth, but is new information on an important subject.

Advertisements

Seagrass Meadows support big fisheries

Research has recently shown that seagrass meadows play an important role in world fisheries productivity. A fifth of the world’s largest fisheries, such as Atlantic Cod and Walleye Pollock are reliant on seagrass meadows. With this in mind we should be looking at managing and maintaining the meadows to maximize fish production.

Seagrasses are marine flowering plants that form extensive meadows in shallow seas around the world , except the Antarctic. The distribution of seagrasses from intertidal to about 60 meters in-depth in clear water, makes these meadows exploitable. The importance of the meadows is to provide nursery habitat for commercial fish stocks such as tiger prawns, conch, Atlantic Cod, and the white spotted spinefoot. The meadows also fisheries in adjacent and deep water habitats.

Policy relevant observations and recommendations include:

Seagrass nursery habitats for fish stocks.

Seagrass as prime fishing grounds.

Seagrass provides shallow water habitat for harvesting invertebrates.

The potential value of seagrass meadows for food security.

 

Day Zero…the injury report

We have looked at the drought situation in the Cape Town area of South Africa before…but there is a new twist with injured Capetonians.

There is a new phrase in the Cape Town lingo..Day Zero injuries. Lugging buckets of grey water from the showers and washing machines to be recycled in the gardens or in the loo is causing injuries. These injuries can range from minor to serious, even requiring surgery. Physiotherapists are doing great business.

Neck, shoulder, elbow and wrist issues are prominent. People carrying heavy buckets of water in awkward positions are getting stressed. Less physically active people seem at most risk, usually the tendons get damaged.

The problem started back in January when due to severe drought conditions Capetonians were told they were going to have to make due with 50l of water per day.

The sale of buckets went up. The population was going to have to recycle water. The drought has lessened and the day when the taps run dry, Day Zero, has most likely been put off this year. Restrictions remain so the bucket regime is being maintained.

One reason why people are getting injured is because of using smaller buckets people are using bigger buckets and filling them all the way up. When pouring these buckets  they are quite often in awkward positions and thus injuries occur. Consider 20l of water weighs 20kgs.

Tips for Capetonians…

Bend knees, keep the load close to the body, avoid spilling and slipping..do not rush. make a few trips, use good quality buckets, use a trolley where possible.

 

Freshwater is changing around the world

A new study of Earth’s freshwater distribution found the Earth’s wet areas are getting wetter, and the dry areas are getting dryer. A variety of factors are being considered as the causes..human water management practices, human caused climate change, natural climate cycles.

The NASA lead research team used 14 yrs of observations from the Gravity Recovery and Climate Experiment mission (GRACE) to track global trends in 34 areas worldwide.

Freshwater availability was assessed using satellite observations. A key goal was to determine if shifts in terrestrial water storage  were caused by natural means(El Nino/La Nina) or from trends related to climate change or human impact (pumping out too much groundwater)

A major hydrological change is being noted…wet areas are getting wetter and the dry areas are getting dryer. This change was predicted in the intergovernmental Panel on Climate Change Models for the end of the 21st century. The current trajectory is cause for concern.

The Grace satellite data can’t tell what is causing the trend.

One of the big causes for groundwater depletion is agriculture. Decreases in ground water could be seen to support agriculture in areas of drought.  This was seen in California and Saudi Arabia.

Natural cycles of rainy and dryer yrs also cause trends in the 14 yr records. Combinations of natural and human pressures can also make a difference.

The successor to the Grace satellites is called Grace Follow On…and it is presently undergoing final preparations for launch. More science to follow.

The Baltic Sea

The Baltic Sea is fairly shallow, has low salinity, and has only a small connection to the Atlantic Ocean and so you would think it would not be very interesting to scientists working on global ocean topics. Think again. This unique sea can serve us as kind of a time machine to better estimate future global changes.

 

 

The argument is that changes that we can expect in the future global ocean can be witnessed today in the Baltic. The relatively small body of water  has a slow water exchange with the open ocean, thus things are amplified, processes and interactions occur at a faster pace. An example of this is that the oceans have warmed by .5c over the last 30 yrs…but the Baltic has warmed by 1.5c. There are also large oxygen free zones in large areas of the deep Baltic, these areas have increased 10x over the last 100 yrs. PH, the measure of acidity of the ocean water, regularly reaches levels that we only expect to see in the open ocean in the next 100 yrs.

There are two main reasons for these changes. The first is the actual topography or the geography particular to the Baltic Sea. The second is the large and growing human presence in the area surrounding the sea.

Interestingly, the Baltic is one of the best surveyed bodies of water in the world. Scientific monitoring and observations began over 100 yrs ago.The countries surrounding have a strong tradition of scientific cooperation. There is good scientific data available.

Management success stories are the large drop in nutrient production since the 1980’s reversing the decline in large predators,  Overfishing has been addressed with increases in fish stock, marine mammals, and bird populations noted.

Essentially with overfishing, warming, acidification, pollution, eutrophication, loss of oxygen, and intensive use of coasts  we see factors  noted all around the world. Due to its geography in the world the Baltic has seen all this and some of the key problems have been addressed, the region for bad or good, can tell us what to expect and how to respond in the future.

The Baltic Sea contributing to the United Nation’s Sustainable Development Goal 14…the conservation and sustainable use of the oceans, seas, and marine resources.

Contaminants in Wastewater

A Canadian national review was recently published dealing with the contaminants in wastewater. Opportunities for a more strategic, risk based approach to investments was highlighted.

The experts noted that keeping contaminants out of municipal wastewater systems through source control is more effective than trying to remove them from the waste water. We have seen over the past decade an increase in contaminants in wastewater which can have an adverse effect on public and environmental health.

In the past waste water treatment systems were designed to treat human organic waste. Today’s waste has increased in complexity and the difficulties of dealing with it has increased. We now see pathogens, nutrients, metals, drugs, and microplastics.

The experts were challenged with determining which contaminants were the priorities, available treatment options, and possible trade offs and opportunities.

The Canadian way of handling wastewater changes across the country…Canadians who live on the coast have different challenges than those living on the prairies who have different issues than those in the arctic.

It looks like we need an integrated watershed approach that considers upstream investments such as nutrient offsetting, we need flexibility in tech selection, and look at wastewater treatment plants as resource recovery facilities.

The report also concludes that Canada’s approach to the new waste water challenges is not going to be a simple one size fits all, there needs to be a comprehensive  management strategy addressing complex risks and multiple uncertanties.

 

New Brunswick the Great Flood of 2018

The big news in water this week in Canada has come out of New Brunswick and the St. John River Valley. The latest if the Coast Guard has been called to assist with flood relief work as water levels are continuing to rise.

The unprecedented flood levels, up to 8 meters in the Fredericton area, have led to hundreds of evacuations and great damage to property.  In the second week of flooding  the danger to the southern half of the province is still growing. Water levels in St. John are expected to be at 5.9 meters by Monday.

The Fredericton water levels are 1.5 meters above flood levels, The weather forecast calls for them to start receding by Tuesday.

Water everywhere…what a contrast to the severs drought being experienced elsewhere in the world.