Difficulties in tracking the long-term global trend in tropical forest area.

The long-term trend in tropical forest area receives less scrutiny than the tropical deforestation rate. We show that constructing a reliable trend is difficult and evidence for decline is unclear, within the limits of errors involved in making global estimates. A time series for all tropical forest area, using data from Forest Resources Assessments (FRAs) of the United Nations Food and Agriculture Organization, is dominated by three successively corrected declining trends. Inconsistencies between these trends raise questions about their reliability, especially because differences seem to result as much from errors as from changes in statistical design and use of new data. A second time series for tropical moist forest area shows no apparent decline. The latter may be masked by the errors involved, but a "forest return" effect may also be operating, in which forest regeneration in some areas offsets deforestation (but not biodiversity loss) elsewhere. A better monitoring program is needed to give a more reliable trend. Scientists who use FRA data should check how the accuracy of their findings depends on errors in the data.

Extinction risk from climate change.

Climate change over the past approximately 30 years has produced numerous shifts in the distributions and abundances of species and has been implicated in one species-level extinction. Using projections of species' distributions for future climate scenarios, we assess extinction risks for sample regions that cover some 20% of the Earth's terrestrial surface. Exploring three approaches in which the estimated probability of extinction shows a power-law relationship with geographical range size, we predict, on the basis of mid-range climate-warming scenarios for 2050, that 15-37% of species in our sample of regions and taxa will be 'committed to extinction'. When the average of the three methods and two dispersal scenarios is taken, minimal climate-warming scenarios produce lower projections of species committed to extinction ( approximately 18%) than mid-range ( approximately 24%) and maximum-change ( approximately 35%) scenarios. These estimates show the importance of rapid implementation of technologies to decrease greenhouse gas emissions and strategies for carbon sequestration.

Comment on "The global tree restoration potential".

Bastin et al (Reports, 5 July 2019, p. 76) neglect considerable research into forest-based climate change mitigation during the 1980s and 1990s. This research supports some of their findings on the area of land technically suitable for expanding tree cover, and can be used to extend their analysis to include the area of actually available land and operational feasibility.

Telephone announcements encouraging common cold self-management reduce demand for general practice appointments.

BACKGROUND: Patients consulting with the common cold contribute to seasonal demand for general practice appointments. Seeing a community pharmacist or using self-management may have been more appropriate options. The study aimed to measure if the use of telephone announcements signposting appropriate patients with the common cold in the direction of community pharmacy or self-management reduced demand for general practice consultations. METHODS: Patients telephoning a UK general practice to request an appointment between December 2017 and March 2018 heard announcements regarding management of the common cold. The percentage of callers choosing to continue to speak to a receptionist was compared with baseline data prior to the intervention. The mean waiting time to the third available routine general practice appointment during the intervention was compared with the previous year. RESULTS: Routine calls continuing to reception reduced by 5.5 % (p<0.001) when the incidence of the common cold is at its highest and by 3.9% (p<0.001) throughout the intervention. The mean waiting time to the third available routine appointment reduced by 21%. CONCLUSION: This study has demonstrated that the use of telephone announcements signposting appropriate patients with the common cold in the direction of community pharmacy or self-management reduces calls to reception. This strongly infers that the telephone announcements reduce demand for general practice appointments and is supported by the reduced mean waiting time to the third available routine appointment. Implementation of this intervention could help general practitioners reduce seasonal demand in their own practices.

The extent of forest in dryland biomes.

Dryland biomes cover two-fifths of Earth's land surface, but their forest area is poorly known. Here, we report an estimate of global forest extent in dryland biomes, based on analyzing more than 210,000 0.5-hectare sample plots through a photo-interpretation approach using large databases of satellite imagery at (i) very high spatial resolution and (ii) very high temporal resolution, which are available through the Google Earth platform. We show that in 2015, 1327 million hectares of drylands had more than 10% tree-cover, and 1079 million hectares comprised forest. Our estimate is 40 to 47% higher than previous estimates, corresponding to 467 million hectares of forest that have never been reported before. This increases current estimates of global forest cover by at least 9%.