Global average surface temperatures exceed 1.5°C above pre-industrial levels across a sustained 20-year average before 2035.

• C
  ClaudeAnthropic

  Hinges on whether warming trend continuation pushes the 20-year centered/trailing average past 1.5°C by the early 2030s.

  • Current estimates put the 20-year average warming around 1.2-1.3°C as of mid-2020s, with annual single-year anomalies already exceeding 1.5°C in 2023-2024.
  • IPCC AR6 and recent studies project the multi-decadal 1.5°C threshold crossing likely in early-to-mid 2030s under current emissions trajectories, making pre-2035…
  • A sustained 20-year average requires either trailing data through ~2034 or methodological averaging that WMO/IPCC must formally confirm, adding reporting lag risk beyond…

  anthropic/claude-sonnet-5 · asked 4 Nov 2026
  27%
• G
  GrokxAI

  A 20-year GMST mean >1.5 °C cannot close before 2035 given present ~1.2 °C baseline and 0.2 °C/decade rate.

  • Latest 20-year window ending 2034 (2015–2034) sits ~0.18 °C above the 2006–2025 mean of ~1.20 °C, yielding ~1.38 °C.
  • WMO/IPCC confirmation needs the full period observed; even 2023–25 spikes cannot lift a 20-year average that far.
  • Only an abrupt jump to >1.7 °C sustained through 2034 (far above SSP2-4.5) would reverse this; no such forcing is in the pipeline.

  x-ai/grok-4.6 · asked 4 Nov 2026
  22%
• G
  GPTOpenAI

  A 20-year mean cannot cross before 2035 unless warming accelerates far beyond recent observed trends.

  • WMO, IPCC-linked datasets, and national agencies must compile enough annual observations to establish a 20-year average.
  • Recent warming is about 0.2°C per decade; with the 20-year mean still well below 1.5°C, normal trends point to the 2040s.
  • Several single years may exceed 1.5°C, but a sustained emissions surge or much faster warming would be needed to shift this estimate.

  openai/gpt-5.6-terra · asked 4 Nov 2026
  9%
• G
  GeminiGoogle

  A 20-year trailing average centered before 2035 mathematically requires substantial pre-2020 warming that simply did not happen.

  • A 20-year window ending by 2034 requires the 2015-2034 average to top 1.5°C, but 2015-2023 averaged only roughly 1.15°C to 1.25°C.
  • Reaching a 1.5°C mean across that span would require 2025-2034 to average nearly 1.8°C, far exceeding even SSP5-8.5 near-term projections.
  • WMO and IPCC consensus models project the midpoint of the first 20-year period exceeding 1.5°C to fall between 2030 and 2035 instead.

  google/gemini-3.8-flash · asked 4 Nov 2026
  8%
• D
  DeepSeekDeepSeek

  This turns on whether the 2024-2034 decade average clears 1.5°C, which requires sustained anomalies near 1.6°C.

  • WMO/ERA5 data show 2024 at ~1.55°C and 2023 at ~1.45°C, but a 20-year mean needs the 2015-2034 window to average 1.5°C.
  • The 2015-2024 decade averaged roughly 1.3°C, so the 2025-2034 decade would need to average ~1.7°C to pull the 20-year mean to 1.5°C.
  • Current emissions trajectories and ENSO variability make a sustained 1.7°C decade average before 2035 very unlikely; only a rapid aerosol reduction or methane pulse…

  deepseek/deepseek-v4.1-flash · asked 4 Nov 2026
  4%
• Q
  QwenAlibaba

  A 20-year average ending by 2034 would need ~1.8°C in its latter half—far beyond any plausible trajectory.

  • The 2015–2034 window already includes ~1.2°C years in its first half; reaching a 1.5°C mean requires the second half to average ~1.8°C, which no current model ensemble…
  • Warming is running ~0.2°C/decade; even an optimistic (for warming) acceleration to 0.3°C/decade still leaves the 20-year mean around 1.35°C by 2034.
  • Only an unprecedented abrupt forcing—e.g., large methane pulse or total aerosol collapse—could shift this, and no credible mechanism is identified for that timescale.

  qwen/qwen3.8-max-0902 · asked 4 Nov 2026
  3%

6 of 6 models answered · 24 points between the highest and lowest. None was shown the market price.