get_dailytemp {hockeystick}

Download and plot essential climate data

Description

Retrieves the daily air or sea-surface temperature data since 1979 from ClimateReanalyzer.org Source is University of Maine Climate Change Institute. https://climatereanalyzer.org/clim/t2_daily/

Usage

get_dailytemp(
  use_cache = TRUE,
  write_cache = getOption("hs_write_cache"),
  region = "W",
  mean_start = if (region %in% c("WS", "NS", "ws", "ns")) 1982 else 1979,
  mean_end = 2000
)

Arguments

use_cache

(boolean) Return cached data if available, defaults to TRUE. Use FALSE to fetch updated data.

write_cache

(boolean) Write data to cache, defaults to FALSE. Use TRUE to write data to cache for later use. Can also be set using options(hs_write_cache=TRUE)

region

(string) Region selection, defaults to world air temperature. Options are: World Air "W", Northern Hemisphere Air "NW", Southern Hemisphere Air "SW", Tropics Air "TR", Arctic Air "AR", Antarctica Air "AN", World Sea Surface "WS", and North Atlantic Sea Surface "NS".

mean_start

(numeric) Start year for historic mean, defaults to 1979.

mean_end

(numeric) End year for historic mean, defaults to 2000.

Value

Invisibly returns a tibble with the daily 2-meter air or sea surface temperatures since 1940 as well as historic mean by day-of-year and current anomaly versus mean.

get_dailytemp invisibly returns a tibble with the daily temperatures since 1940 as well as mean by day-of-year and anomaly. Default to world data, but region can be selected among six options.

Region options include world air (default), Northern Hemisphere air, Southern Hemisphere air, Tropics air, Arctic air, Antarctic air, World sea surface and North Atlantic sea surface and is stored in attribute of output. The historic daily mean-by-day period defaults to 1979-2000. This range can be optionally modified.

Data are updated daily. For day-of-year mean removes observations from February 29 on leap years.

Author(s)

Hernando Cortina, [e-mail]

References

• ClimateReanalyzer.org: https://climatereanalyzer.org/clim/t2_daily/

  Notes: daily mean surface air temperature (2-meter height) estimates from the ECMWF Reanalysis version 5 (ERA5) for the period January 1940 to present. ERA5 is a state-of-the-art numerical climate/weather modeling framework that ingests surface, radiosonde, and satellite observations to estimate the state of the atmosphere through time. ERA5 files have a horizontal grid resolution of 0.25° x 0.25° (about 31km x 31km at 45°N). Each daily temperature represents an average across all model gridcells within the defined latitude/longitude bounds for the selected domain. The means are area-weighted to account for the convergence of longitude lines at the poles

Examples

# Fetch temp anomaly from cache if available:
dailytemps <- get_dailytemp()
#
# Force cache refresh:
dailytemps <- get_dailytemp(use_cache=FALSE)
#
# Review cache contents and last update dates:
hockeystick_cache_details()
#
# Plot output using package's built-in ggplot2 settings
plot_dailytemp(dailytemps)

# Change region to Arctic
arctictemp <- get_dailytemp(region='AR', use_cache=FALSE)