How Will the National Park Service Protect America’s Heritage from Climate Change?

Marcy Rockman, an archaeologist with the National Park Service (NPS) likes to say that “Every place has a climate story.” And telling those stories, as well as effectively responding to the growing risks, is central to an ambitious new strategy to manage the nation’s cultural resources in a rapidly changing climate.

The Cultural Resources Climate Change Strategy (CRCCS) was just published on January 6; Rockman was the lead author. It addresses climate change across the National Park System and is aimed at helping park managers and scientists plan and implement responses, and not least, communicate the scale of the problem to the public.

Climate is now the greatest threat to national parks

NPS Director Jon Jarvis, who retired this week, called climate change “fundamentally the greatest threat to the integrity of our national parks that we have ever experienced.” During his tenure he positioned the park service as a leader and innovator among US agencies in responding to the climate challenge.

The NPS has established climate monitoring and impact assessment programs and in 2009 established a multi-disciplinary Climate Change Response Program. In 2010, the NPS published its first Climate Change Response Strategy, laying out the four pillars of a comprehensive approach: science, adaptation, mitigation, and communication.

The publication of the CRCCS builds on the goals of the 2010 strategy and provides practical follow-up to a 2014 policy memorandum in which Jarvis noted that “Climate change poses an especially acute problem for managing cultural resources because they are unique and irreplaceable — once lost, they are lost forever.

The NPS is the lead cultural resource agency for the federal government. In addition to the National Park system it holds responsibility for programs including the National Register of Historic Places (including more than 1.4 million buildings, sites, monuments, and structures), National Scenic and Historic Trails, National Heritage Areas, and the American Battlefield Protection Program. It also administers the Federal Historic Preservation Tax Incentives Program.

Cultural resources covered in the new strategy include archaeological sites, buildings and structures, museum collections, ethnographic resources (heritage traditionally important to diverse cultural groups), museum collections and cultural landscapes. The NPS recognizes not only the threat to cultural resources from climate, but also that these resources can provide vital information and data regarding human responses to climatic and environmental changes in the past, and in this way potentially contribute to adaptation and resilience strategies for the future.

We can learn from the past, to become more resilient in the future

Archaeological evidence from Wupatki National Monument in northern Arizona shows that the local Sinagua people responded to a volcanic eruption and subsequent decades long shift to a drier climate by moving to the plains below the crater where they began to farm using volcanic cinder mulch to maintain soil moisture and increase crop productivity.

At San Juan National Historic site in Puerto Rico, modern technology has been combined with 18^th-century water engineering to restore seven underground cisterns in Castillo San Felipe del Morro and Castillo San Cristóbal to support sustainable water use.

And in Mount Rainier, in response to increased flooding driven by climate change, engineers have turned away from the modern use of riprap (boulder embankments) which was proving ineffective and begun using engineered log-jams and log structure techniques reminiscent of those used in the early 20^th century to repair roads and control erosion.

The new CRCCS notes with some understatement that “it is difficult to learn from cultural resources, develop adaptation strategies for them, or incorporate them into mitigation plans if they have been damaged or destroyed.” And they are being damaged and destroyed—from Fort Jefferson in Florida’s Dry Tortugas National Park to the eroding 4,000-year-old Inupiat Eskimo sites at Cape Krusenstern National Monument in Alaska.

The CRCCS identifies 21 categories of direct and indirect climate change interactions that are already or will in the future affect cultural resources, including:

• Increased temperature
• Changed freeze/thaw cycles
• Permafrost thawing
• Higher relative humidity
• Increased wildfires
• Changes in seasonality and phenology
• Species shift
• Changes in precipitation patterns and extreme weather events
• Increased flooding, inundation and coastal erosion
• Higher water tables
• Salt water intrusion

Examples of impacts identified by the NPS include sea level rise and damage to the wooden foundation of the Cockspur Lighthouse at Fort Pulaski National Monument in Georgia, erosion of Native American shell mound sites at Canaveral National Seashore in Florida, and risk of increasing wildfire damage to archaeological resources in Yosemite and Mesa Verde National Parks. Changing rainfall patterns and more intense downpours have already severely damaged the more than 200-year-old adobe Franciscan church in Tumacácori National Historic Park in southern Arizona.

Stephanie Meeks, president and CEO at the National Trust for Historic Preservation (NTHP, a close UCS partner in launching the Climate Heritage Coalition) applauded the launch of the report saying,  “At a time when more and more of our nation’s irreplaceable historic resources are experiencing the impacts of climate change…This report provides timely and essential guidance to both NPS managers and historic preservation partners to anticipate, plan for, and respond to the effects of a changing climate on our shared cultural heritage.”

Cultural heritage in every national park is at risk

The consequences of climate change for cultural resources identified in the new report are quite staggering in their diversity and comprehensiveness. So much so that it is hard to escape the conclusion the NPS makes that “it is likely that cultural resources in all park units are or will be affected by climate change in some way.”

Whilst the impacts of sea level rise, coastal erosion, storm surge, and increasing wildfires have been well documented in reports such as UCS’s National Landmarks at Risk, the CCRS highlights many lesser-known impacts too. A small sampling of those described in the report includes:

• Damage to foundations and stone-work because of increased frost heaving, waterlogging, thawing permafrost, or drought
• Cracking, spalling, warping, and cracking of masonry and other building materials
• Historic building drainage systems unable to cope with increased extreme rainfall events
• Collapse of caves and bedrock alcoves
• Flaking and abrasion of petroglyphs and pictoglyphs
• Accelerated deterioration of organic material such as paper, wood, paintings, fabric, and animal skins
• Increased mold, especially in enclosed sites such as vaults, tumuli, and caves
• Loss or shifting range of culturally important species (e.g. walrus, salmon, piñon pine)
• Reduction or loss of medicinal and ceremonial plants used during particular times of the year
• Altered appearance of important ceremonial sites
• Changes in view-sheds
• Spread of destructive plats and insects such as termites and kudzu to threaten structures
• Submerged sites exposed due to lower water levels
• Increased risk of looting from exposure (as with eroding coastal sites, lowering lake levels and melting ice patches)
• Inundation and submersion of traditional homelands and consequent loss of social connections and interactions
• Disassociation of historic districts and settings due to pressure to relocate or elevate structures
• Increased erosion of limestone and mortar structures, and lime or shell cliffs resulting from ocean acidification
• Increased risk of damage to shipwrecks due to loss of protective concretions and or coral reefs (resulting from ocean acidification and warming)

Given the huge array of potential impacts and the sheer number of resources under the care of the NPS, the CRCCS lays out some guidelines for addressing the scale of the problem. For example, it notes that there is now a clear need to integrate global and local climate change data and projections into all cultural resource management and planning. This is being done, for example, at Tumacácori. Having seen the unexpected damage to the church from extreme rainfall, NPS cultural resource managers, material scientists and climate researchers are now working closely together to understand fine-scale local climate patterns and their implications for the historic structures in the park.

In addition to site-specific guidance, the CRCCS provides some important broad-scale policy recommendations, including:

• Take urgent steps to target survey and documentation programs to evaluate resources, assess their vulnerabilities, and prioritize options to respond before they are lost
• Develop guidance to relate historic preservation legislation and programs to climate change adaptation
• Integrate cultural resources into Disaster Preparedness and Response (noting that climate change will unfold as a long string of disasters of varying rates and intensities, and that good planning can assist in disaster recovery when such events and impacts occur)
• Incorporate cultural resources in sustainability and climate change mitigation efforts by maximizing the energy efficiency of historic buildings through continued maintenance and continuing to add energy efficiency and renewable energy methods to historic buildings and landscapes (referencing the work of the NTHP Preservation Green Lab)
• Consider contemporary significance of potential historic resources through consultation with diverse stakeholders.

We must prioritize because not everything can be saved

As noted above, the CRCCS explicitly recognizes that it will not be possible to save or protect all the cultural resources under the mandate of the NPS, and that a process of vulnerability assessment and prioritization will have to be undertaken, both nationally and at the individual site level.

Scenario planning has been adopted by the NPS to develop climate responses and strategies that are robust in the face of varying levels of uncertainty regarding the rate and scale of specific climate impacts and their interactions with each other, and with other environmental stressors.

Prioritization involves assessing climate vulnerability across resources in a park, assessing the level of importance or significance of each resource at risk, reviewing adaptation options, and then making implementation decisions.

Such a process had already begun at Gateway National Recreation Area in New York City and New Jersey when Hurricane Sandy struck. Gateway includes Fort Hancock, along with gun batteries, airfields, missile silos, nine historic districts, and more than 600 historic structures, and attracts nearly 10 million visitors annually. Prior to Sandy, the park authorities had used characteristics such as resource condition, public use potential, and uniqueness to identify three categories of cultural resource, those that should be preserved, those that should be stabilized to minimize impacts, and those that could be left to deteriorate or be lost. The pre-storm categorization was later updated and combined with data assessing Sandy’s damage patterns and new flood mapping to guide reconstruction after the storm and to form the basis for the park’s new General Management Plan.

Yellowstone, Grand Teton, and Shenandoah National Parks, the National Capital Region of the NPS and Cape Lookout National Seashore, among others, are now also carrying out various prioritization processes for their cultural resources.

At Cape Lookout, where two historic villages on the barrier islands are at high risk from rising sea levels, NPS staff have partnered with researchers from North Carolina State University, Western Carolina University, the US Geological Survey Southeast Climate Science Center, the North Carolina State Historic Preservation Office, and local community members to assess adaptation options. The range of potential options for action include no intervention, offsetting stress, relocation, and documentation in advance of permanent loss.

Climate stories can help push back against denialists in Washington D.C.

The NPS is at the forefront of climate vulnerability assessment and response internationally, as UCS documented in its recent joint report on climate change and World Heritage sites with UNESCO and UNEP.

The CRCCS identifies as a key strategy the importance of connecting with partners both in the US and globally to learn and share innovations in cultural resource management in the face of climate change. From the Oxford Rock Breakdown Laboratory in the UK (with its focus on climate impacts on historic stonework), to the Integrated History and Future of People on Earth (IHOPE) project which is dedicated to learning from the past to assist future resilience, the NPS is increasing its coordination with international projects wherever possible.

One of several innovations the NPS is bringing to the table which has not been developed elsewhere is climate change literacy and interpretation training programs for park managers and rangers.

With more than 300 million visitors annually, our national parks offer an unprecedented opportunity to bring the best available climate science directly to the American people in ways that that they can easily understand and in places that they care deeply about.

When all is said and done, the new communications goals that the CRCCS lays out for researching and writing climate stories for each national park and incorporating them in interpretation, outreach, and educational materials, may be among its most important contributions. It may be these stories that help to push back the current wave of climate denial in Washington by bringing home to Americans who love their national parks what we stand to lose if we don’t act decisively to slow climate change.

###

N.B. I would like to acknowledge advice and input for this blog from Anthony Veerkamp (Field Director, San Francisco Office) and Jeana Wiser (Senior Manager, Resilient Communities, Preservation Green Lab) of the National Trust for Historic Preservation. All opinions and any errors are my own.