presented in Table 1.5 and also illustrated in Fig. 1.6
(IITM-ESM). The qualifiers to express certainty in the
assessments are presented in Box 1.4.
Box 1.4: Qualifiers to Express Certainty in
Assessment Findings
Two qualifiers have been used in this assessment
report to express the degree of certainty in key
findings.
• Confidence is a qualitative expert judgement by the
authors based on an evaluation of available information in terms of 1. The amount, quality and
consistency of evidence and 2. Agreement within
the surveyed literature.
Confidence levels (based on IPCC):
• Very high: Robust evidence, high agreement.
• High: Robust evidence, medium agreement; Medium evidence, high agreement.
• Medium: Medium evidence, medium agreement.
• Low: Limited evidence, low agreement.
Broad criteria adopted in this Report to gauge
‘evidence’:
• >3 scientific papers: Robust evidence;
• 2–3 scientific papers: Medium evidence;
• 2 scientific papers: Limited evidence;
• 1 scientific paper: Insufficient evidence.
Broad criteria adopted in this Report to gauge
‘agreement’:
• >70% agreement in surveyed literature: High
agreement;
• 50–70% agreement in surveyed literature: Medium
agreement;
• 30–50% agreement in surveyed literature: Low
agreement;
• <30% agreement in surveyed literature: No
agreement.
Confidence cannot be interpreted statistically.
• Likelihood is a quantitative measure of uncertainty
based on the probability of an outcome or result
based on a statistical analysis of observational data
or modelling outcomes or on the authors’ expert
judgement.
Likelihood levels (adopted from IPCC):
• Virtually certain: 99–100% probability;
• Very likely: 90–100%;
• Likely: 66–100%;
• About as likely as not: 33–66%;
• Unlikely: 0–33%;
• Very unlikely: 0–10%;
• Exceptionally unlikely: 0–1%.
See for more details: Mastrandrea, M. D., C.
B. Field, T. F. Stocker, O. Edenhofer, K. L. Ebi, D.
J. Frame, H. Held, E. Kriegler, K. J. Mach,
P. R. Matschoss, G.-K. Plattner, G. W. Yohe and F.
W. Zwiers 2010: Guidance Note for Lead Authors of
the IPCC Fifth Assessment Report on Consistent
Treatment of Uncertainties, Intergovernmental Panel on
Climate Change (IPCC), Geneva, Switzerland, 4 pp.
1.3 Scope of the Report
This report provides a detailed overview and synthesis of the
published scientific literature on climate change over India
and adjoining regions. The objectives are to provide a
state-of-the-art assessment of how and why India’s climate is
changing, changes that are projected for the future, uncertainties and knowledge gaps, and identification of areas that
require greater research.
The scope of this report is the physical science basis of
climate change with a focus on regional climate drivers
specific to the Indian land area and the surrounding ocean. It
is a region-focused analogue of the global scale assessment
by Working Group I of the Intergovernmental Panel on
Climate Change.
This report will be useful to advance public awareness of
India’s changing climate and to inform mitigation and
adaptation decision making. While it is meant to be policy
relevant, this report is not intended to be policy prescriptive.
This report is organized as follows: Chapters 2 and 3
focus on observed and projected trends in the mean and
extremes of temperature and precipitation. Chapters 4 and 5
quantify the spatial and temporal variations in GHG fluxes
and concentrations, and climate forcing due to anthropogenic aerosol emissions and trace gases over India.
Chapter 6 discusses the observed and projected changes in
1 Introduction to Climate Change Over the Indian Region
15
(IITM-ESM). The qualifiers to express certainty in the
assessments are presented in Box 1.4.
Box 1.4: Qualifiers to Express Certainty in
Assessment Findings
Two qualifiers have been used in this assessment
report to express the degree of certainty in key
findings.
• Confidence is a qualitative expert judgement by the
authors based on an evaluation of available information in terms of 1. The amount, quality and
consistency of evidence and 2. Agreement within
the surveyed literature.
Confidence levels (based on IPCC):
• Very high: Robust evidence, high agreement.
• High: Robust evidence, medium agreement; Medium evidence, high agreement.
• Medium: Medium evidence, medium agreement.
• Low: Limited evidence, low agreement.
Broad criteria adopted in this Report to gauge
‘evidence’:
• >3 scientific papers: Robust evidence;
• 2–3 scientific papers: Medium evidence;
• 2 scientific papers: Limited evidence;
• 1 scientific paper: Insufficient evidence.
Broad criteria adopted in this Report to gauge
‘agreement’:
• >70% agreement in surveyed literature: High
agreement;
• 50–70% agreement in surveyed literature: Medium
agreement;
• 30–50% agreement in surveyed literature: Low
agreement;
• <30% agreement in surveyed literature: No
agreement.
Confidence cannot be interpreted statistically.
• Likelihood is a quantitative measure of uncertainty
based on the probability of an outcome or result
based on a statistical analysis of observational data
or modelling outcomes or on the authors’ expert
judgement.
Likelihood levels (adopted from IPCC):
• Virtually certain: 99–100% probability;
• Very likely: 90–100%;
• Likely: 66–100%;
• About as likely as not: 33–66%;
• Unlikely: 0–33%;
• Very unlikely: 0–10%;
• Exceptionally unlikely: 0–1%.
See for more details: Mastrandrea, M. D., C.
B. Field, T. F. Stocker, O. Edenhofer, K. L. Ebi, D.
J. Frame, H. Held, E. Kriegler, K. J. Mach,
P. R. Matschoss, G.-K. Plattner, G. W. Yohe and F.
W. Zwiers 2010: Guidance Note for Lead Authors of
the IPCC Fifth Assessment Report on Consistent
Treatment of Uncertainties, Intergovernmental Panel on
Climate Change (IPCC), Geneva, Switzerland, 4 pp.
1.3 Scope of the Report
This report provides a detailed overview and synthesis of the
published scientific literature on climate change over India
and adjoining regions. The objectives are to provide a
state-of-the-art assessment of how and why India’s climate is
changing, changes that are projected for the future, uncertainties and knowledge gaps, and identification of areas that
require greater research.
The scope of this report is the physical science basis of
climate change with a focus on regional climate drivers
specific to the Indian land area and the surrounding ocean. It
is a region-focused analogue of the global scale assessment
by Working Group I of the Intergovernmental Panel on
Climate Change.
This report will be useful to advance public awareness of
India’s changing climate and to inform mitigation and
adaptation decision making. While it is meant to be policy
relevant, this report is not intended to be policy prescriptive.
This report is organized as follows: Chapters 2 and 3
focus on observed and projected trends in the mean and
extremes of temperature and precipitation. Chapters 4 and 5
quantify the spatial and temporal variations in GHG fluxes
and concentrations, and climate forcing due to anthropogenic aerosol emissions and trace gases over India.
Chapter 6 discusses the observed and projected changes in
1 Introduction to Climate Change Over the Indian Region
15