We are back from hiatus!! Thanks for hanging in there with us through our travels! This summer will have a lot more travels in store for our “Global ArchaeoVenturers” Series! – Stay tuned for the rest of Season 3 & more ‘in the field’ footage!
No matter which camp you side with in the ‘Climate Change’ discussion, its effects cannot be denied.period. Polar vortexes, massive flooding, snow in deserts, excessive drought, etc… we’ve all been privy to it the last few years no matter where we are in this world, in the extreme, and whether it happens sooner or later, these changes will continue unchecked. However, without getting into said debate, this blog & episode is about how climate change is not just affecting our atmospheres, oceans, and seas, but as a byproduct- our submerged heritage as well. If you’re a maritime archaeologist, a scuba diver, someone fascinated by shipwrecks or just someone interested in the past- this means you should be concerned for all of the knowledge that could potentially be lost because of climate change affecting the preservation and ability to document submerged sites.
The author diving on a WWII shipwreck in Santorini
The problem with underwater heritage is that it is by definition, underwater, meaning that many times these sites are ‘out of sight, out of mind’ for even those already concerned with cultural heritage protection. Because of a desperate need for awareness and additional protection even within our own sector, UNESCO had to expand upon the 1970 Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property by creating a completely separate (and needed) Convention on the Protection of the Underwater Cultural Heritage in 2001. Heritage managers are already fighting great odds to protect submerged sites, and now climate change is complicating that fight even more because the answers aren’t clear and the solutions may not even be feasible.
As Katie (The Digger) asks in this episode, how can things like rising sea levels make a difference for a site that is already underwater? Well rising sea levels create two problems- 1. sites that are not yet submerged, but may soon be. Even with the right protection, many of these sites are location specific and whole settlements that cannot be moved – Jamestown V.A.- the site of the first English settlement in America or the Statue of Liberty in NYC, amongst others, are predicted to be underwater within another 100 years! What can be done to prevent this? If people would cut their carbon emissions, it could slow down the rate of these predictions of sea level and temperature rises. 2. For sites already underwater, as discussed in the episode (all other environmental factors aside), a rise in water level on sites significantly reduces the amount of time that divers/maritime archaeologists can spend on the site. This might not seem like as big of a deal, but when you take into consideration how costly an underwater archaeological excavation already is, then if the time spent on a site continues to reduce, a full study could take years longer. English Heritage archaeologist Mark Dunkley describes “the effect of sea level rise on archaeological diving projects will be to incrementally reduce the amount of time (and therefore productivity) an air-breathing diver can spend underwater safely. For example, a 20% increase in diving depth can result in a 32% decrease in dive time.” Not to forget that the deeper a site gets, the more expensive high tech equipment will be needed for proper documentation.
Teredo navalis (shipworm type) in wood
If you refer to an earlier blog
“Forgotten Legacy of WWII Wrecks- Environmental Hazard or Underwater Cultural Heritage?” you’ll recall why the scientific world is also concerned because “shipwrecks, ocean acidification and waste dumping into oceans are among the biggest sources of ocean pollution. Some 75% of sunken wrecks date back to the Second World War; their metal structures are therefore ageing and the plates deteriorating, threatening to release their contents into the ocean under the effect of corrosion. The North Atlantic Ocean has 25% of the potentially polluting wrecks in the world, which can contain up to 38% of the total volume of oil trapped in sunken vessels” says
the Council of Europe in 2012.Other impacts of climate change on marine environments include increased seawater temperatures, ocean acidification and changes in ocean circulation which will also affect underwater cultural heritage. The National Oceanic and Atmospheric Administration (NOAA) uses
underwater WWII shipwrecks in North Carolina to monitor changes in the marine ecosystems that these ships support as the waters warm up. “North Carolina’s marine communities are made up of a mixture of temperate and tropical species, due to the states’ geographic location in a transition zone between north and south.” So far, they have seen an increase in tropical animals off N.C. as well as tropical algae species never before seen in the area. Invasive species like the notoriousshipworm
(which is actually a mollusk) which has a penchant for boring into and living in submerged wooden structures, are spreading from their native habitats and thriving in the warming seas. As far north as the U.K. Dunkley points out
that the blacktip shipworm has now become active all-year round on unprotected shipwrecks because of sea temperature increase. A report on shipworm invasions in the Baltic Sea by David Gregory for UNESCO illustrates
that these dangers to wooden vessels have spread possibly beyond repair in an environment once conducive to pristine wreck preservation, specifically because of the absence of marine borers. These species are an ever-growing major threat to wooden wrecks and structures.
These numbers are meant to be intimidating. Humanity is so concerned (and rightfully so) with losing our cultural heritage through force and violence, like in the cases with ISIS going on right now, but what happens when we sit by and do nothing, knowing the effects of climate change today on the future of submerged sites? Will we be mournful for the unknown knowledge or the lives left unremembered on the bottom of the sea because we didn’t get out acts together in time before the information was lost? We must make more strides to understand the impacts/effects of climate change and create ocean management strategies that incorporate cultural heritage, for it is necessary to help us manage the maritime historic environment for future generations.
Watch this week’s accompanying episode entitled “How Does Climate Change Affect Shipwrecks?” HERE
or visit youtube.com/ArchaeoVenturers