---
activity_duration: 4 hours
computing_environment: Mac OS 10.11
data_usage: ~
dataset_variables: ~
duration: 4 hours
end_time: 2016-12-31T00:00:00
href: https://data.globalchange.gov/activity/nca4-km3-figure-process.yaml
identifier: nca4-km3-figure-process
interim_artifacts: OMR_F4.ai
methodologies: []
methodology: 'For the 2012 and 2014-15 blobs, <br/>1. Data were downloaded for the optimally interpolated SST from NOAA (OI SST, Reynolds et al. 2007 R. W. Reynolds et al., Daily high-resolution-blended analyses for sea surface temperature. J. Climate 20, 5473, from http://www.ncei.noaa.gov).  <br/>2. Monthly means were calculated to compile a monthly climatology over the period 1982-2011.  <br/>3. Monthly anomalies were computed by subtracting the climatology from the monthly mean.  <br/>4. "Heatwaves” were then defined: a monthly temperature anomaly > 2 times the Standard Deviation (SD) (2*SD), where the SD is the standard deviation of data at that location (1982-2011) during that month that persisted for two months or more. (see Matlab function “findheatwaves_mnth.m”).<br/>4. At each location, the longest stretch of consecutive heatwaves between 2012 and 2016 were defined (longestheatwave.m).'
methodology_citation: ~
methodology_contact: 'Andrew Pershing, Gulf of Maine Research Institute'
modified_source_location: ~
notes: |-
  undefinedOptimum Interpolation Sea Surface Temperature (OISST) https://www.ncdc.noaa.gov/oisst
  
   image: 65565f51-8d2a-455d-b1a0-d9366d0a153a
output_artifacts: OMR_F4.ai
publication_maps:
  - activity_identifier: nca4-km3-figure-process
    child: 31721
    child_uri: /publication/31721
    note: ''
    parent: 21807
    parent_uri: /publication/21807
    relationship: prov:wasDerivedFrom
software: Matlab R2016b
source_access_date: ~
source_modifications: 'Monthly means were calculated for a subset of the dataset period of record, over the period of 1982-2011.'
spatial_extent: '{"type":"Feature","bbox":[-180,-90,180,90],"properties":{},"geometry":{"type":"Polygon","coordinates":[[[-180,-90],[180,-90],[180,90],[-180,90],[-180,-90]]]}}'
start_time: 2012-01-01T00:00:00
uri: /activity/nca4-km3-figure-process
visualization_methodology: |-
  Start dates for heatwaves longer than 8 months were mapped and are included in the image file named “Dates” layer of OMR_F4.ai.
  
  The 2016 Alaska section is a result of tracing over Figure 9.1b from Oliver et al. (2018)  (Anthropogenic and natural influences on record 2016 marine heat waves. Bulletin of the American Meteorological Society 99:S44-S48).
  
  The names of impacted species for each of the 2012 (Mills et al. 2013), 2015 (McCabe et al. 2017) and 2016 (Barbeaux et al. 2017) were added.
visualization_software: 'Matlab R2016b,Adobe Illustrator CC 2017'