Editing IPCC:Wg1:Chapter:Chapter-1-comments (section)

===== ''1.5.1.1.4 Biosphere'' =====

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Satellite observations have recently expanded to include data on the fluorescence of land plants as a measure of photosynthetic activity via the Global Ozone Monitoring Experiment (GOME; [[#Guanter--2014|Guanter et al., 2014]] ; [[#Yang--2015|Yang et al., 2015]] ) and OCO-2 satellites ( [[#Sun--2017|Sun et al., 2017]] ). Climate data records of leaf area index (LAI), characterizing the area of green leaves per unit of ground area, and the fraction of absorbed photosynthetically active radiation (FAPAR) – an important indicator of photosynthetic activity and plant health ( [[#Gobron--2009|Gobron et al., 2009]] ) – are now available for over 30 years ( [[#Claverie--2016|Claverie et al., 2016]] ). In addition, key indicators such as fire disturbances/burned areas are now retrieved via satellite ( [[#Chuvieco--2019|Chuvieco et al., 2019]] ). In the US, the National Ecological Observational Network (NEON) provides continental-scale observations relevant to the assessment of changes in aquatic and terrestrial ecosystems via a wide variety of ground-based, airborne, and satellite platforms ( [[#Keller--2008|Keller et al., 2008]] ). All these long-term records reveal range shifts in ecosystems ( [[IPCC:Wg1:Chapter:Chapter-2#2.3.4|Section 2.3.4]] ).

The ability to estimate changes in global land biomass has improved due to the use of different microwave satellite data ( [[#Liu--2015|Liu et al., 2015]] ) and in situ forest census data and co-located lidar, combined with the Moderate Resolution Imaging Spectroradiometer (MODIS; [[#Baccini--2017|Baccini et al., 2017]] ). This has allowed for improved quantification of land temperature ( [[#Duan--2019|Duan et al., 2019]] ), carbon stocks and human-induced changes due to deforestation (Chapter 2, [[IPCC:Wg1:Chapter:Chapter-2#2.2.7|Section 2.2.7]] ). Time series of Normalized Difference Vegetation Index (NDVI) from MODIS and other remote-sensing platforms is widely applied to assess the effects of climate change on vegetation in drought-sensitive regions ( [[#Atampugre--2019|Atampugre et al., 2019]] ). New satellite imaging capabilities for meteorological observations, such as the advanced multispectral imager aboard Himawari-8 ( [[#Bessho--2016|Bessho et al., 2016]] ), also allow for improved monitoring of challenging quantities such as seasonal changes of vegetation in cloudy regions ( [[IPCC:Wg1:Chapter:Chapter-2#2.3.4.3|Section 2.3.4.3]] ; [[#Miura--2019|Miura et al., 2019]] ).

In the ocean, efforts are underway to coordinate observations of biologically relevant EOVs around the globe ( [[#Muller-Karger--2018|Muller-Karger et al., 2018]] ; [[#Canonico--2019|Canonico et al., 2019]] ) and to integrate observations across disciplines (e.g., the Global Ocean Acidification Observing Network, GOA-ON; [[#Tilbrook--2019|Tilbrook et al., 2019]] ). A large number of coordinated field campaigns during the 2015/2016 El Niño event enabled the collection of short-lived biological phenomena such as coral bleaching and mortality caused by a months-long ocean heatwave ( [[#Hughes--2018|Hughes et al., 2018]] ); beyond this event, coordinated observations of coral reef systems are increasing in number and quality ( [[#Obura--2019|Obura et al., 2019]] ). Overall, globally coordinated efforts focused on individual components of the biosphere (e.g., the Global Alliance of Continuous Plankton Recorder Surveys, GACS; [[#Batten--2019|Batten et al., 2019]] ) contribute to improved knowledge of the ways in which marine ecosystems are changing ( [[IPCC:Wg1:Chapter:Chapter-2#2.3.4.2|Section 2.3.4.2]] ).

Given widespread evidence for decreases in global biodiversity in recent decades – and that these decreases are related to climate change and other forms of human disturbance ( [[#IPBES--2019|IPBES, 2019]] ) – a new international effort to identify a set of Essential Biodiversity Variables (EBVs) is underway ( [[#Pereira--2013|Pereira et al., 2013]] ; [[#Navarro--2017|Navarro et al., 2017]] ).

In summary, the observational coverage of ongoing changes to the climate system is improved at the time of AR6, relative to what was available for AR5 ( ''hi'' ''gh confidence'' ).

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