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The prolonged 2012–2016 California drought has raised many issues including concerns over reduced vegetation health. Drought impacts are complicated by geographical differences in hydroclimatic variability due to a climatic dipole influenced by the Pacific. Analysis of MODIS‐derived Normalized Difference Vegetation Index and self‐calibrated Palmer Drought Severity Index from 2000 to 2018 reveals differences in drought and vegetation responses in Northern versus Southern California (NorCal vs SoCal, see definition in section ). The greatest declines in Normalized Difference Vegetation Index were focused in the SoCal, while NorCal appears not severely affected thus far. It appears that both the strength of drought and the sensitivity of the vegetation to drought are larger in SoCal. The exacerbated aridity in SoCal is a trend extending throughout the past and present century. The spatial differences in hydroclimatology and vegetation responses are important considerations for statewide climate change adaptation—with SoCal potentially facing greater challenges.

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Ecosystems in Mediterranean climates are adapted to seasonal drought. Multiannual drought, however, may significantly affect Mediterranean ecosystems and, further, may affect their constituent communities in different ways with differences in responses emerging during severe drought and over the course of long‐term climate change. This study investigates the response to recent prolonged drought of two important Mediterranean‐climate vegetation types: chaparral and coastal sage scrub. Their greenness was monitored from 2000 to 2017 using the Normalized Difference Vegetation Index (NDVI) derived from the Moderate Resolution Imaging Spectroradiometer. A bootstrapped multiple regression of NDVI anomalies against Palmer Drought Severity Index was used to assess the response of vegetation to drought. The results suggest that drought had a greater effect on chaparral‐dominated ecosystems than coastal sage over the entire region. Shallow‐rooted coastal sage scrub displayed higher interannual variability in NDVI than chaparral but had a lower correlation with Palmer Drought Severity Index. This suggests that this vegetation community is generally less responsive to drought on longer timescales than chaparral, which may be more sensitive to soil water depletion in a prolonged drought. Soil texture plays a critical role in affecting the community sensitivity to drought. For chaparral communities, elevation is negatively correlated with drought sensitivity, suggesting the role of temperature‐related water stress on their long‐term response to drought. Future predicted climate change in the form of increased temperature and drought hazards in Southern California will influence the native ecosystems in nonuniform ways. Long‐term trends in soil moisture depletion and temperature may be particularly important in chaparral‐dominated areas.

There has been a rapid evolution of satellites, sensors, and techniques to measure, monitor, and manage terrestrial protected areas. There are over 100,000 protected areas around the world and most lack important information on the status and trends of natural resource issues. We review advances and limitations in spaceborne remote sensing that can be applied to all terrestrial protected areas around the world. There have been significant advances in baseline vegetation mapping and land cover classifications by combining field data, data from multiple sensors, and classification techniques. However, global classifications on the extent of non-forest vegetation types (e.g. grasslands and shrublands) are still needed at 30 m pixel resolution. High spatial (< 1 m) and spectral (220 bands) resolution sensors have provided important data on environmental issues (e.g. invasive species, degradation) that are region or site specific. Advances in monitoring protected areas have primarily focused on forest ecosystems and land cover dynamics in and around protected areas using time series data. Landsat imagery can be used to monitor vegetation extent and dynamics at 30 m pixel resolution across the globe, while the MODIS sensors are more appropriate for monthly updates on trends of ecosystem health in protected areas. There has also been an increase in time series remote sensing datasets on anthropogenic impacts, such as light pollution, fire, and land surface temperature, that can be used for all protected areas. Future geographic research should focus on developing global protocols and incorporating near real time and annual metrics that can easily be used by natural resource managers to assess the status and trends of all protected areas.