q51·intermediate

How have rainfall and temperature changed over my region in recent decades?

atmosphereclimatehydrology Datasets: 3 5–15 min via Google Earth Engine

✓ Verified answer Real ERA5 trends, computed on Google Earth Engine.

Area-weighted Theil–Sen slope + Mann–Kendall significance. Most regional rainfall trends are statistically flat (an earned null); Indo-Gangetic-Plain temperature shows significant warming. Computed, not yet scientist-verified.

Has annual rainfall in the Marathwada region declined from 1990 to 2020?

rainfall Marathwada 1990–2020

-1.183 mm/year (trend) no significant trend

95% CI [-8.646, 7.167] Mann–Kendall p = 0.6341

The data doesn't support a rainfall change here — an earned null, not a missing answer.

⚠ Ground-truth: gauges disagree IMD gauges ↓ · ERA5 ↑ · CHIRPS ↑ sources DISAGREE on direction — treat the trend as unresolved. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over the Indo-Gangetic Plain changed from 1980 to 2020?

temperature Indo-Gangetic Plain 1980–2020

+0.016 degC (trend) significant trend

95% CI [0.003, 0.03] Mann–Kendall p = 0.0059

Prior: IMD/IPCC consensus: India land-surface warming ~0.6-0.7C/century, accelerating.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has rainfall over the Western Ghats crest meaningfully changed from 1991 to 2020?

rainfall Western Ghats crest 1991–2020

-0.245 mm/year (trend) no significant trend

95% CI [-16.379, 16.596] Mann–Kendall p = 1

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Rainfall trend over Punjab, 1990-2020?

rainfall Punjab 1990–2020

-5.799 mm/year (trend) no significant trend

95% CI [-12.603, 1.898] Mann–Kendall p = 0.1739

The data doesn't support a rainfall change here — an earned null, not a missing answer.

⚠ Ground-truth: gauges disagree IMD gauges ↓ · ERA5 ↓ · CHIRPS ↑* sources DISAGREE on direction — treat the trend as unresolved. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Rainfall trend over Kerala, 1990-2020?

rainfall Kerala 1990–2020

+6.541 mm/year (trend) no significant trend

95% CI [-4.858, 15.146] Mann–Kendall p = 0.1438

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑* all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

What was the mean annual rainfall over the Krishna basin, 2000-2020?

rainfall Krishna basin 2000–2020

1129.3mm/year

computed · ERA5/GEE · not yet scientist-verified

Has monsoon-season (JJAS) rainfall over central India changed from 1990 to 2020?

rainfall Central India 1990–2020

+1.23 mm/year (trend) no significant trend

95% CI [-9.445, 13.019] Mann–Kendall p = 0.6341

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Tamil Nadu changed from 1990 to 2020?

rainfall Tamil Nadu 1990–2020

+4.088 mm/year (trend) no significant trend

95% CI [-5.939, 12.906] Mann–Kendall p = 0.3412

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑* all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Tamil Nadu changed from 1980 to 2020?

temperature Tamil Nadu 1980–2020

+0.02 degC (trend) significant trend

95% CI [0.011, 0.031] Mann–Kendall p = 0

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Karnataka changed from 1990 to 2020?

rainfall Karnataka 1990–2020

+1.402 mm/year (trend) no significant trend

95% CI [-4.89, 9.295] Mann–Kendall p = 0.6341

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Karnataka changed from 1980 to 2020?

temperature Karnataka 1980–2020

+0.02 degC (trend) significant trend

95% CI [0.009, 0.029] Mann–Kendall p = 0

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Gujarat changed from 1990 to 2020?

rainfall Gujarat 1990–2020

+8.447 mm/year (trend) no significant trend

95% CI [-4.367, 17.172] Mann–Kendall p = 0.1347

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑* · CHIRPS ↑* all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Gujarat changed from 1980 to 2020?

temperature Gujarat 1980–2020

+0.018 degC (trend) significant trend

95% CI [0.009, 0.026] Mann–Kendall p = 0.0007

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Rajasthan changed from 1990 to 2020?

rainfall Rajasthan 1990–2020

+1.414 mm/year (trend) no significant trend

95% CI [-4.819, 7.13] Mann–Kendall p = 0.5184

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑* all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Rajasthan changed from 1980 to 2020?

temperature Rajasthan 1980–2020

+0.013 degC (trend) significant trend

95% CI [0, 0.03] Mann–Kendall p = 0.0338

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over West Bengal changed from 1990 to 2020?

rainfall West Bengal 1990–2020

-6.59 mm/year (trend) no significant trend

95% CI [-16.478, 4.77] Mann–Kendall p = 0.1534

The data doesn't support a rainfall change here — an earned null, not a missing answer.

⚠ Ground-truth: gauges disagree IMD gauges ↓* · ERA5 ↓ · CHIRPS ↑ sources DISAGREE on direction — treat the trend as unresolved. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over West Bengal changed from 1980 to 2020?

temperature West Bengal 1980–2020

+0.018 degC (trend) significant trend

95% CI [0.006, 0.026] Mann–Kendall p = 0.0007

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Madhya Pradesh changed from 1990 to 2020?

rainfall Madhya Pradesh 1990–2020

+0.524 mm/year (trend) no significant trend

95% CI [-6.436, 11.043] Mann–Kendall p = 0.8918

The data doesn't support a rainfall change here — an earned null, not a missing answer.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Madhya Pradesh changed from 1980 to 2020?

temperature Madhya Pradesh 1980–2020

+0.016 degC (trend) significant trend

95% CI [0.006, 0.028] Mann–Kendall p = 0.0013

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Odisha changed from 1990 to 2020?

rainfall Odisha 1990–2020

+3.624 mm/year (trend) no significant trend

95% CI [-15.228, 13.977] Mann–Kendall p = 0.5634

The data doesn't support a rainfall change here — an earned null, not a missing answer.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Odisha changed from 1980 to 2020?

temperature Odisha 1980–2020

+0.01 degC (trend) significant trend

95% CI [0.002, 0.017] Mann–Kendall p = 0.0052

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Assam changed from 1990 to 2020?

rainfall Assam 1990–2020

-20.4 mm/year (trend) significant trend

95% CI [-36.556, -0.498] Mann–Kendall p = 0.0249

✓ Ground-truth: gauges agree IMD gauges ↓ · ERA5 ↓ · CHIRPS ↓ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Assam changed from 1980 to 2020?

temperature Assam 1980–2020

+0.024 degC (trend) significant trend

95% CI [0.017, 0.031] Mann–Kendall p = 0

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑* all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over the Delhi NCR changed from 1990 to 2020?

rainfall Delhi NCR 1990–2020

+0.094 mm/year (trend) no significant trend

95% CI [-7.46, 7.186] Mann–Kendall p = 1

The data doesn't support a rainfall change here — an earned null, not a missing answer.

⚠ Ground-truth: gauges disagree IMD gauges ↓* · ERA5 ↑ · CHIRPS ↑ sources DISAGREE on direction — treat the trend as unresolved. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over the Delhi NCR changed from 1980 to 2020?

temperature Delhi NCR 1980–2020

+0.009 degC (trend) no significant trend

95% CI [-0.005, 0.026] Mann–Kendall p = 0.1965

The data doesn't support a temperature change here — an earned null, not a missing answer.

Prior: IMD/IPCC consensus: India land-surface warming.

⚠ Ground-truth: gauges disagree IMD gauges ↑ · ERA5 ↓ sources DISAGREE on direction — treat the trend as unresolved. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has annual rainfall over Mumbai & the Konkan coast changed from 1990 to 2020?

rainfall Mumbai & Konkan 1990–2020

+10.047 mm/year (trend) no significant trend

95% CI [-13.514, 28.655] Mann–Kendall p = 0.3412

The data doesn't support a rainfall change here — an earned null, not a missing answer.

✓ Ground-truth: gauges agree IMD gauges ↑ · ERA5 ↑ · CHIRPS ↑ all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

How has average temperature over Mumbai & the Konkan coast changed from 1980 to 2020?

temperature Mumbai & Konkan 1980–2020

+0.022 degC (trend) significant trend

95% CI [0.015, 0.03] Mann–Kendall p = 0

Prior: IMD/IPCC consensus: India land-surface warming.

✓ Ground-truth: gauges agree IMD gauges ↑* · ERA5 ↑* all sources agree on direction. IMD = India Meteorological Dept. gauge grid (the ground-truth); * = significant.

computed · ERA5/GEE · not yet scientist-verified

Has the daytime land-surface temperature over the Delhi NCR risen since 2003?

land-surface temperature Delhi NCR 2003–2022

-0.015 degC (trend) no significant trend

95% CI [-0.054, 0.029] Mann–Kendall p = 0.3145

The data doesn't support a land-surface temperature change here — an earned null, not a missing answer.

Prior: urban heat island + regional warming.

computed · ERA5/GEE · not yet scientist-verified

Has the daytime land-surface temperature over Mumbai risen since 2003?

land-surface temperature Mumbai & Konkan 2003–2022

-0.088 degC (trend) significant trend

95% CI [-0.132, -0.033] Mann–Kendall p = 0.0008

Prior: coastal city; warming likely but sea-moderated.

computed · ERA5/GEE · not yet scientist-verified

Has growing-season greenness (NDVI) over Punjab changed since 2003?

greenness (NDVI) Punjab 2003–2022

+0.003 NDVI (trend) significant trend

95% CI [0.002, 0.004] Mann–Kendall p = 0.0001

computed · ERA5/GEE · not yet scientist-verified

Has growing-season greenness (NDVI) over the Indo-Gangetic Plain changed since 2003?

greenness (NDVI) Indo-Gangetic Plain 2003–2022

+0.003 NDVI (trend) significant trend

95% CI [0.001, 0.003] Mann–Kendall p = 0

computed · ERA5/GEE · not yet scientist-verified

…and what it refuses to answer

What is the rainfall trend over Maharashtra from 2018 to 2021?

rainfall Central India 2018–2021

⊘ Refused

trend span < 10y — the validator refuses ill-posed questions rather than guessing. That discipline is the point.

validator-enforced refusal

How has temperature changed in 'the valley' since 1990?

temperature 1990–2020

⊘ Asks to clarify

unresolved region name — the validator refuses ill-posed questions rather than guessing. That discipline is the point.

validator-enforced refusal

Has it gotten hotter and drier over Vidarbha since 1990?

AMBIGUOUS_MULTI Vidarbha 1990–2020

⊘ Splits the question

answer temperature and precipitation separately — the validator refuses ill-posed questions rather than guessing. That discipline is the point.

validator-enforced refusal

See all verified answers →

▶ Find the data for your area

Draw a rectangle to pick your area of interest, then see what NASA data covers it (live, here in your browser) or download a ready-to-run notebook with your AOI pre-filled. The notebook runs in any Python environment — it needs a free Earthdata Login to fetch the data.

Current AOI: 74, 18 → 80, 22 (Marathwada, Maharashtra)

## What you can answer - **Has rainfall or temperature changed over a region across recent decades?** — an area-weighted **Theil–Sen** slope with **Mann–Kendall** significance and a 95% confidence interval, with precipitation cross-checked **ERA5 vs CHIRPS**. - The honest **null**: "no significant trend" is a real, useful answer here — not a failure. Several regions below land exactly there.

What you can answer

Has rainfall or temperature changed over a region across recent decades? — an area-weighted Theil–Sen slope with Mann–Kendall significance and a 95% confidence interval, with precipitation cross-checked ERA5 vs CHIRPS.
The honest null: “no significant trend” is a real, useful answer here — not a failure. Several regions below land exactly there.

What you can NOT answer (yet)

Attribution (“is this human-caused or natural variability?”) — that needs formal detection-and-attribution, well beyond a single trend.
Daily / sub-seasonal extremes — this is annual (or seasonal JJAS/DJF) trend analysis, not extreme-event statistics.
Trends shorter than ~10 years — the validator refuses them: too few points to trust a slope.

Verified answers

Real ERA5 trends, computed on Google Earth Engine and shown verbatim below — most regional rainfall trends are statistically flat (an earned null), while Indo-Gangetic-Plain temperature shows significant warming. These are computed, not yet scientist-verified. Draw your own area of interest and download the notebook to reproduce the method for your region.

⚲ How a scientist answers this

Parameters

ERA5 2 m temperature (°C/decade) and total precipitation (mm/yr/decade), aggregated to annual or seasonal (JJAS/DJF) means/totals over a region; CHIRPS rainfall as an independent precip cross-check; ERA5-Land for finer land detail. Baseline is the region's own record; trends shorter than ~10 years are refused.

Method

Build the area-weighted annual/seasonal series, then fit an area-weighted Theil–Sen slope with Mann–Kendall significance and a 95% confidence interval; report 'no significant trend' as a valid, earned null when the slope's CI spans zero.

Validation

Cross-check ERA5 precipitation trends against CHIRPS (and gauges where available), state the analysis period explicitly, and avoid over-interpreting short records or claiming attribution — trend detection is not formal detection-and-attribution.

In plain EnglishAverage temperature and rainfall over your region each year, then test whether the long-term line truly tilts up or down beyond natural wobble — and accept 'no real change' as a genuine answer.

Make it yours → Draw your area of interest, choose annual or seasonal windows and the year range, and switch ERA5↔CHIRPS for the rainfall cross-check.

⌨ Run the core method · no login

The robust trend (Theil–Sen + Mann–Kendall) at the heart of this question — runnable on synthetic data, right here. The full earthaccess code template further down does it on real NASA data (needs an Earthdata login).

editable · runs in your browser

import numpy as np, pymannkendall as mk
from scipy.stats import theilslopes
rng = np.random.default_rng(0)
years = np.arange(2001, 2023)
# real code returns this after area-weighting a data cube; here it's synthetic so it runs.
series = 100 - 0.8*(years - 2001) + rng.normal(0, 12, years.size)   # edit slope/noise & rerun
s, _, lo, hi = theilslopes(series, years); r = mk.original_test(series)
print(f"trend {s:+.2f}/yr   (95% CI {lo:+.2f} .. {hi:+.2f})   Mann-Kendall p={r.p:.3f}")
print(">>>", "significant" if r.h else "no significant trend (an earned null)")