1 Contents: Page 3: November 2020 global surface air temperature overview Page 4: November 2020 global surface air temperature overview versus November last 10 years Page 5: November 2020 global surface air temperature compared to November 2019 Page 6: Temperature quality class 1: Lower troposphere temperature from satellites Page 7: Temperature quality class 2: HadCRUT global surface air temperature Page 8: Temperature quality class 3: GISS and NCDC global surface air temperature Page 11: Comparing global surface air temperature and satellite-based temperatures Page 12: Global air temperature linear trends Page 13: Global temperatures: All in one, Quality Class 1, 2 and 3 Page 15: Global sea surface temperature Page 18: Ocean temperature in uppermost 100 m Page 20: North Atlantic heat content uppermost 700 m Page 21: North Atlantic temperatures 0-800 m depth along 59N, 30-0W Page 22: Global ocean temperature 0-1900 m depth summary Page 23: Global ocean net temperature change since 2004 at different depths Page 24: La Niña and El Niño episodes Page 25: Troposphere and stratosphere temperatures from satellites 2 Page 26: Zonal lower troposphere temperatures from satellites Page 27: Arctic and Antarctic lower troposphere temperatures from satellites Page 28: Temperature over land versus over oceans Page 29: Arctic and Antarctic surface air temperatures Page 32: Arctic and Antarctic sea ice Page 36: Sea level in general Page 36: Global sea level from satellite altimetry Page 38: Global sea level from tide gauges Page 39: Snow cover; Northern Hemisphere weekly and seasonal Page 41: Atmospheric specific humidity Page 42: Atmospheric CO2 Page 43: Relation between annual change of atm. CO2 and La Niña and El Niño episodes Page 44: Phase relation between atmospheric CO2 and global temperature Page 45: Global air temperature and atmospheric CO2 Page 49: Latest 20-year QC1 global monthly air temperature change Page 50: Sunspot activity and QC1 average satellite global air temperature Page 51: Climate and history: 1932: First navigation of the Northeast Passage without wintering November 2020 global surface air temperature overview General: This newsletter contains graphs and The year 1979 has been chosen as starting point in diagrams showing a selection of key meteorological many diagrams, as this roughly corresponds to both variables, if possible updated to the most recent the beginning of satellite observations and the onset past month. All temperatures are given in degrees of the late 20th century warming period. However, Celsius. several of the data series have a much longer record length, which may be inspected in greater detail on In the maps on pages 4-5, showing the geographical www.climate4you.com. pattern of surface air temperature anomalies, the last previous 10 years are used as reference period. November 2020 surface air temperature The rationale for comparing with this recent period instead of the official WMO so-called ‘normal’ General: For November 2020 GISS supplied 16200 period 1961-1990, is that the latter period is AIRS interpolated surface air data points, based on affected by the cold period 1945-1980. Most satellite observations and here visualised on pages comparisons with this period will inevitably appear 4-5. According to most global temperature as warm, and it will be difficult to decide if modern databases, the November 2020 global average air temperatures are increasing or decreasing. temperature anomaly was somewhat higher than in Comparing instead with the last previous 10 years the previous month. overcomes this problem and clearer displays the modern dynamics of ongoing change. This decadal The Northern Hemisphere 10-yr temperature approach also corresponds well to the typical anomality pattern (p.4) was characterised by memory horizon for many people and is now also regional contrasts, mainly controlled by the adopted as reference period by other institutions, dominant jet stream configuration. Eastern USA, e.g. the Danish Meteorological Institute (DMI). much of Europe and Siberia had temperatures 3 above the 10-yr average. Especially parts of In addition, most temperature databases display northern Siberia were warm, a fact probably partly temporal instability for data before the turn of the derived from a late formation of the sea ice cover century (see, e.g., p. 9). Any comparison with the around the Taymyr Promontory. See also pages 51- WMO reference period 1961-1990 will therefore be 53 for an analogous effect of sea ice cover in the influenced by such ongoing monthly changes of past. In contrast, most of Canada, India and western mainly administrative nature. An unstable value is Asia had temperatures below the 10-yr average. clearly not suited as reference value. Simply Ocean wise, most of the Greenland Sea, Norwegian comparing with the last previous 10 years is more Sea, and North Atlantic was relatively cold, while useful as reference for modern changes. See also parts of the North Pacific Ocean were relatively additional reflections on page 47. warm. In the Arctic, generally warm conditions prevailed in the Europe-Siberian sectors, while the The different air temperature records have been North American sector was relatively cold. divided into three quality classes, QC1, QC2 and QC3, respectively, as described on page 9. Near the Equator temperatures were mostly near or below (especially in the Pacific Ocean) the 10-year In many diagrams shown in this newsletter the thin average. line represents the monthly global average value, and the thick line indicate a simple running average, The Southern Hemisphere temperatures were in most cases a simple moving 37-month average, largely near or below the average for the previous nearly corresponding to a three-year average. The 10 years. Only major parts of South America and 37-month average is calculated from values most of Australia had temperatures above the 10-yr covering a range from 18 months before to average. In the Antarctic a mixture of relatively cold 18 months after, with equal weight given to all and warm conditions characterised the situation. individual months. Ocean wise, temperatures were relatively low, except for regions between Australia and New Zealand, and east of the Antarctic Peninsula. November 2020 global surface air temperature overview versus average November last 10 years 4 November 2020 surface air temperature compared to the average of November over the last 10 years. Green-yellow-red colours indicate areas with higher temperature than the 10-year average, while blue colours indicate lower than average temperatures. Data source: Remote Sensed Surface Temperature Anomaly, AIRS/Aqua L3 Monthly Standard Physical Retrieval 1-degree x 1-degree V006 (https://airs.jpl.nasa.gov/), obtained from the GISS data portal (https://data.giss.nasa.gov/gistemp/maps/index_v4.html). November 2020 global surface air temperature compared to November 2019 5 November 2020 surface air temperature compared to November 2019. Green-yellow-red colours indicate regions where the present month was warmer than last year, while blue colours indicate regions where the present month was cooler than last year. Variations in monthly temperature from one year to the next has no tangible climatic importance but may nevertheless be interesting to study. Data source: Remote Sensed Surface Temperature Anomaly, AIRS/Aqua L3 Monthly Standard Physical Retrieval 1-degree x 1-degree V006 (https://airs.jpl.nasa.gov/), obtained from the GISS data portal (https://data.giss.nasa.gov/gistemp/maps/index_v4.html). Temperature quality class 1: Lower troposphere temperature from satellites, updated to November 2020 Global monthly average lower troposphere temperature (thin line) since 1979 according to University of Alabama at Huntsville, USA. The 6 thick line is the simple running 37-month average. Global monthly average lower troposphere temperature (thin line) since 1979 according to according to Remote Sensing Systems (RSS), USA. The thick line is the simple running 37-month average. Temperature quality class 2: HadCRUT global surface air temperature, updated to October 2020 Global monthly average surface air temperature (thin line) since 1979 according to according to the Hadley Centre for Climate Prediction 7 and Research and the University of East Anglia's Climatic Research Unit (CRU), UK. The thick line is the simple running 37-month average. Temperature quality class 3: GISS and NCDC global surface air temperature, updated to November 2020 Global monthly average surface air temperature since 1979 according to according to the National Climatic Data Center (NCDC), USA. The 8 thick line is the simple running 37-month average. Global monthly average surface air temperature (thin line) since 1979 according to according to the Goddard Institute for Space Studies (GISS), at Columbia University, New York City, USA, using ERSST_v4 ocean surface temperatures. The thick line is the simple running 37- month average. A note on data record stability and -quality: important that the sensors on satellites measure temperature directly by emitted radiation, while The temperature diagrams shown above all have most modern surface temperature measurements 1979 as starting year. This roughly marks the are indirect, using electronic resistance. beginning of the recent episode of global warming, after termination of the previous episode of global Everybody interested in climate science should cooling from about 1940. In addition, the year 1979 gratefully acknowledge the big efforts