National Park Management


The National Park Service uses critical loads to:

  • guide management decisions
  • help develop Resource Stewardship Strategies
  • influence environmental policy
  • respond to permits for new emission sources near park units

What are the steps for identifying sensitive resources?

While each process uses the data slightly differently, the steps for identifying sensitive resources are generally the same: 

  1. identify resources at risk from N and S pollution
  2. identify which resources are in exceedance of their critical load
  3. identify where in the park the exceedances are occurring


Access the relevant websites and a step-by-step guide for using each website.

WHAT ARE CRITICAL LOADS AND WHY DO THEY MATTER?

overview of how N and S pollution impact ecosystems

IDENTIFY RESOURCES AT RISK FROM N OR S AIR POLLUTION

provides CL values and CL exceedances in a single place for all NPS units

NPS PARK AIR PROFILES

descriptions of resources with critical loads in Class I NPS units

CONDITIONS AND TRENDS OF POLLUTANTS AND ECOSYSTEM HEALTH IN NPS UNITS

for each NPS unit, assesses current resource condition relative to pollution and trends in N and S deposition

REPORTS ON CRITICAL LOADS AND CL EXCEEDANCES WITHIN NPS UNITS

provides access to NADP-CLAD Critical Load Summary reports for each NPS unit

INTERACTIVE MAPS OF CRITICAL LOADS AND EXCEEDANCES

shows the spatial distribution of CLs and CL exceedances across the contiguous US