Abstract
Many regions across the globe broke their surface temperature records in
recent years, further sparking concerns about the impending arrival of
“tipping points” later in the 21st century. This
study analyzes observed global surface temperature trends in three
target latitudinal regions: the Arctic Circle, the Tropics, and the
Antarctic Circle. We show that global warming is accelerating unevenly
across the planet, with the Arctic warming at approximately three times
the average rate of our world. We further analyzed the reliability of
latitude-dependent surface temperature simulations from a suite of
Coupled Model Intercomparison Project Phase 6 models and their
multi-model mean. We found that GISS-E2-1-G and FGOALS-g3 were the
best-performing models based on their statistical abilities to reproduce
observational, latitude-dependent data. Surface temperatures were
projected from ensemble simulations of the Shared Socioeconomic Pathway
2-4.5 (SSP2-4.5). We estimate when the climate will warm by 1.5, 2.0,
and 2.5 ℃ relative to the preindustrial period, globally and regionally.
GISS-E2-1-G projects that global surface temperature anomalies would
reach 1.5, 2.0, and 2.5 ℃ in 2024 (±1.34), 2039 (±2.83), and 2057
(±5.03) respectively, while FGOALS-g3 predicts these “tipping points”
would arrive in 2024 (±2.50), 2054 (±7.90), and 2087 (±10.55)
respectively. Our results reaffirm a dramatic, upward trend in projected
climate warming acceleration, with upward concavity in 21st century
projections of the Arctic, which could lead to catastrophic consequences
across the Earth. Further studies are necessary to determine the most
efficient solutions to reduce global warming acceleration and maintain a
low SSP, both globally and regionally.