Leesylvania State Park Living Shorelines Restoration Update

 Leesylvania State Park Living Shorelines Project was a collaborative regional effort.  The Prince William County Public Works Department's Environmental Services worked with the Virginia Department of Conservation and Recreation, Northern Virginia Regional Commission, Virginia Institute of Marine Science (who designed the project) and the Virginia Association of Parks on the $300,000 project to construct the living shoreline. The project was funded with grants from Dominion Energy and the National Fish and Wildlife Foundation. The design by VIMS was completed and permitted in 2013and the construction was completed in the Summer of 2016.

In June 2016 on behalf of the project NVRC accepted an award from then Governor Terry McAulie designating the project as a Virginia Treasure. The project incorporated “Living Shoreline” practices: sills, marsh restoration, and beach enhancement to balance habitat restoration with shoreline protection and recreational access to the Potomac River. Living shorelines provide an effective and natural looking alternative for protecting shorelines in low wave energy areas, such as the Potomac River and its tidal tributaries.

VIMS is one of the leaders in designing and implementing living shorelines on public and private lands throughout the region. Living Shorelines area more natural approach to shore stabilization that uses marshes, beaches, and dunes to protect the shoreline along Virginia's creeks, rivers, and bays. This approach to shoreline management creats critical habitat for marine plants and animals, improvs water quality, and reduces sedimentation. After four years in place, the project has proved successful at mending  and protecting 800 feet of eroded shoreline in Leesylvania  State Park the Prince William County Press Release reports: 

"Adding sand to renourish the shoreline and planting high marsh switchgrass and the low marsh river bulrush in the sandy beach to create a tidal wetland, as well as installing rock barriers, called sills (that deflect and break up the wave energy of the river), off the shoreline have kept erosion at bay," said Prince William County Department of Public Works Environmental Services Environmental Engineer Tom Dombrowski. "The protected shore is no longer eroding. The beach is actually growing, and the wetlands are healthy."

Additionally, Mr. Dombrowski said, "A living shoreline provides habitat, breeding and spawning areas for aquatic and terrestrial species." The image below is from Google Earth with comments from VMIS in their review of the project. 

Before and after pictures of the restoration from Northern Virginia Regional Commission's report. 

Prince William Soil and Water Conservation District and Prince William County can provide information and assistance if you want to implement Living Shoreline Practices on your property. 

IPCC Releases 5th Climate Report

Today the Intergovernmental Panel on Climate Change (IPCC) has finally released the much anticipated Fifth Assessment Report on climate change. The summaries that had been previously leaked to the traditional press and been reported in the newspapers (and the IPCC released an official summary on Friday) made the actual release of the report less news worthy. As widely reported the IPCC found that despite the current pause in the increase in surface temperature, the planet is warming and it is “extremely likely that the changes in our climate system for the past half a century are due to human influence.”

As the IPCC points out, confidence in the validity of this finding is based on the type, amount, quality, and consistency of evidence. The type of evidence used in the report were data collected in the past century, mechanistic understanding of the earth’s ecology, climate theory, mathematical models built to forecast the climate, and expert judgment. Observations of the climate system are based on direct measurements and remote sensing from satellites. Global-scale observations from the instrumental era began in the mid-19th century predominately for temperature. More comprehensive data has been collected since 1950s.

In their report the IPCC Working Group cites the overwhelming scientific consensus about the causes and results of climate change, but also calls for further assessments and projections, especially at regional level and in the oceans. Multiple lines of evidence confirm to the authors that the extra heat being trapped by greenhouse gases is warming the Earth’s atmosphere, surface, heating and acidifying the oceans, raising sea levels, and melting ice caps and glaciers. The report states the decade 2001-2010 was the warmest on record, a decade in which more temperature records were broken than any previous decade. However, the average surface temperature has actually not increased in the past decade.

from NOAA

For the period of 1970 to 2000 the median surface temperature as recorded by measurements increased 0.3 ± 0.04°F per year. However, there has been little further warming of the surface of the planet, particularly over the oceans in the most recent 10 to 15 years. The start of the current pause is difficult to pin down precisely. Although 1998 is often quoted as the start of the current pause, this was an exceptionally warm year because of the largest El Niño on record. This was followed by a strong La Niña event and a fall in global surface temperature of around 0.36°F which is equal to the average global warming for an entire decade based on the previous 30 years. It is only really since 2000 that the rise in global surface temperatures has paused. According to the Met Office Hadley Centre (MOHC) there is still substantial evidence from the other components of the climate system, beyond the global mean surface temperature, that the Earth has continued to warm over the last decade and this evaluation is supported by the scientific consensus in the IPCC Working Group.

Analysis of simulated natural climate variability by the MOHC using the climate models indicates that even with a long term warming rate of 0.3°F per decade, at least two periods without apparent temperature increase lasting a decade would be expected each century. The current pause in global surface temperature rise is not viewed as exceptional, based on those model simulations. The scientists cite two potential mechanisms to explain the recent pause; the first involves changes to the total energy received by the planet (radiative forcing), and the second involves the low frequency variability of the oceans and the way in which the oceans take up heat and store it below the surface in the deeper ocean. It is possible that a pause in surface warming could result from both mechanisms acting together though according to the MOHC radiative forcing by greenhouse gases has continued unabated; that heat is being held in the system but has not manifest as a rise in global mean surface temperature.

Observations of ocean heat content and of sea-level rise suggest that the additional heat has rather been absorbed in the oceans. Changes in the exchange of heat between the upper and deep ocean appear to have caused at least part of the pause in surface warming especially in the Pacific Ocean. In addition, the scientists point out the relative cooling influence of La Niña weather events. Since 2000 there have been no major El Niño events and indeed the tropical Pacific has been predominantly in La Niña states. These factors were not predicted in previous versions of the climate forecasting models. Thus, the IPCC cites the need for more research especially in the areas of deep sea temperatures.

IPCC and the scientific consensus have pivoted slightly in their focus to the oceans and sea level rise. The IPCC reports a Working Group consensus that ocean warming dominates the increase in energy stored in the earth’s climate system, accounting for more than 90% of the energy accumulated between 1971 and 2010. Since the early 1970s, glacier mass loss and ocean thermal expansion from warming together explain about 75% of the observed global mean sea level rise the rest is assembly attributed to the rise in sea levels that has been occurring unabated for over 10,000 years. “As the ocean warms, and glaciers and ice sheets reduce, global mean sea level will continue to rise, but at a faster rate than we have experienced over the past 40 years,” said Co-Chair Qin Dahe in the IPCC’s press release.

The IPCC Working Group expects global surface temperatures for the end of the 21st century to likely increase 2.7°F to 3.6°F relative to 1850 to 1900 time period. “Heat waves are very likely to occur more frequently and last longer. As the Earth warms, we expect to see currently wet regions receiving more rainfall, and dry regions receiving less, although there will be exceptions,” said Co-Chair Thomas Stocker in the press release. Dr. Stocker concluded his comments by reminding us that as a result of our past, present and expected future emissions of CO2, climate change is inevitable, and will persist for many centuries even if emissions of CO2 were to stop today.

Rising Sea Levels and Shrinking Artic Ice

from NASA to see animation click

In mid-August a draft copy of the Intergovernmental Panel on Climate Change, IPCC, and five year report due to be peer reviewed this coming fall then officially released to the public was leaked to Reuters and the New York Times. The media (both print and Internet) was a buzz despite the fact that the IPCC does not do any original research, but merely summarizes the published scientific literature on climate change. Six years ago the IPCC report predicted a maximum of 23 inches of sea-level rise by the end of this century, but according to the New York Times, the new report lays out several possibilities from as little as 10 inches to a maximum of 21 inches by the end of the century.

These estimates of sea level rise are based on the amount of warming experienced by the plant in response to the increase in greenhouse gases that has already occurred. Even if the entire planet stopped burning fossil fuels tomorrow, the planet would continue to warm. Whatever is going to happen will happen; it is too late to change that. Warming increases sea level in two ways: thermal expansion and the melting of the glaciers and ice caps. When water warms it expands in volume and is expected to contribute a portion of the sea level increase. More than 97% of the Earth’s water is already within the in oceans. The remaining 2.8% of water is the water within the land masses, 2.15% is contained in icecaps and glaciers. The melting of the ice, which has so far been most pronounced in mountain glaciers might increase surface infiltration of water, but the remainder will flow to the oceans increasing sea volume. The big concern is for the future of the ice sheets in the Arctic and Antarctica and what impact the volume of water contained there will have on sea levels.

Last Friday the sea ice minimum analysis produced at NASA’s Goddard space laboratory using satellite data was released. The melting of sea ice in the Arctic reaches its annual minimum, when the ice cap covers less of the Arctic Ocean than at any other period during the year, in the middle of September each year. The good news is that NASA is predicting it is unlikely that this year’s summer low will break a new record. Still, this year’s melt rates are in line with the long term decline of the Arctic ice cover observed by NASA and other satellites over the last several decades. The data record, which began in November 1978, shows an overall shrinking in the size of the Arctic sea ice minimum each summer since 1978 of 14% per decade.

The ice cover in the Arctic Ocean was measured at 2.25 million square miles on Aug. 21. For comparison, the smallest Arctic sea ice extent on record for this date, recorded in 2012, was 1.67 million square miles, and the largest recorded for this date was in 1996, when ice covered 3.16 million square miles of the Arctic Ocean. Though, early summer saw a fast retreat of the sea ice, melting slowed as clouds over the central Arctic kept temperatures cooler than average, and the Arctic experienced mild summer storms. According to Walt Meier, a glaciologist with NASA’s Goddard Space Flight Center in Greenbelt, Maryland: “Last year’s storm went across an area of open water and mixed the smaller pieces of ice with the relatively warm water, so it melted very rapidly. This year, the storms hit in an area of more consolidated ice. The storms this year were more typical summer storms; last year’s was the unusual one.”

In Antarctica, the story is different. Right now, Antarctic sea ice is in the midst of its yearly growing cycle and is heading towards the largest extent on record. Antarctic sea ice reached 7.45 million square miles on Aug. 21. In 2012, the extent of Antarctic sea ice for the same date was 7.08 million square miles. The phenomenon, appears counter-intuitive, and is currently the subject of many research studies. Still, the rate at which the Arctic is losing sea ice surpasses the speed at which Antarctic sea ice is expanding so sea level rise is of great concern to mankind who throughout history has settled along the coast lines.