Estimating the thermal response of streams to a warming climate is important for prioritizing native fish conservation efforts. While there are plentiful estimates of air temperature responses to climate change, the sensitivity of streams, particularly small headwater streams, to warming temperatures is less well understood. A substantial body of literature correlates subannual scale temperature variations in air and stream temperatures driven by annual cycles in solar angle; however, these may be a low-precision proxy for climate change driven changes in the stream energy balance. We analyzed summer stream temperature records from forested streams in the Pacific Northwest for interannual correlations to air temperature and standardized annual streamflow departures. A significant pattern emerged where cold streams always had lower sensitivities to air temperature variation, while warm streams could be insensitive or sensitive depending on geological or vegetation context. A pattern where cold streams are less sensitive to direct temperature increases is important for conservation planning, although substantial questions may yet remain for secondary effects related to flow or vegetation changes induced by climate change.

High‐quality information is needed for conservation and management of aquatic resources on lands administered by the U.S. Forest Service (USFS). Information is ultimately derived from data, so the USFS maintains a series of databases that are used to describe the status and trends of aquatic habitats and biota. The databases are spatially explicit and are crowd‐sourced, meaning that distributed networks of professionals and technicians operating throughout the National Forest System collect stream and biological measurements, which are stored in central repositories. How those databases are developed is evolving and ranges from agency‐specific endeavors to collaborative projects that involve dozens of natural resource organizations and extensive user‐communities throughout the USA. The rate of data collection is accelerating and databases now often encompass millions of records, so proper archiving and maintenance by information technology specialists are necessary to maximize the utility of data for natural resource planning. Here, we describe several of the aquatic databases maintained by the USFS, applications arising from novel syntheses of databases, and the increasingly important roles databases play in collaborative partnerships and cost‐effective stewardship of aquatic resources.

Warming temperatures and prolonged drought periods cause rapid changes of fire frequencies and intensities in high-latitude ecosystems. Associated smoke plumes deposit dark particles from incomplete combustion on the Greenland ice sheet that reduce albedo but also provide a detailed record of paleofire history. Here, we apply an emerging microscopic charcoal technique in combination with established black carbon and lead pollution measurements to an array of 10 ice cores from southern to central Greenland that span recent decades. We found that microscopic charcoal deposition is highly variable among sites, with a few records suggesting recently increasing biomass burning possibly in response to growing fire activity in boreal forest ecosystems. This stands in contrast to decreasing trends in black carbon measured in the same ice cores, consistent with contributions from industrial fossil fuel emissions. Decreasing trends of lead pollution and occurrence of microscopic spheroidal carbonaceous particles (SCP), a microfossil tracer of fossil fuel emissions, further support our interpretation that black carbon in this region is influenced by industrial emissions during recent decades. We conclude that microscopic charcoal analyses in ice may help disentangle biomass burning from fossil-fuel emissions during the industrial period and have potential to contribute to better understanding of regional high-latitude fire regimes.