Quantifying the uncertainty introduced by internal climate variability in projections of Canadian crop production

The study examines how farmers’ observations of climate variability and change correspond with 42 years (1970-2011) meteorological data of temperature and rainfall. It shows how farmers in the Northern Region of Ghana adjust to the changing climate and explore the various obstacles that hinder the implementation of their adaptation strategies. With the help of an extension officer, 200 farmers from 20 communities were randomly selected based on their farming records. Temperatures over the last four decades (1970-2009) increased at a rate of 0.04 (± 0.41) ˚C and 0.3(± 0.13)˚C from 2010-2011 which is consistent to the farmers (82.5%) observations. Rainfall within the districts are characterised by inter-annual and monthly variability. It experienced an increased rate of 0.66 (± 8.30) mm from 1970-2009, which was inconsistent with the farmers (81.5%) observation. It however decreased from 2010-2011 at a huge rate of -22.49 (±15.90) mm which probably was the reason majority of the respondents claim rainfall was decreasing. Only 64.5% of the respondents had adjusted their farming activities because of climate variability and change. They apply fertilizers and pesticides, practice soil and water conservation, and irrigation for communities close to dams. Respondents desire to continue their current adaptation methods but may in the future consider changing crop variety, water-harvesting techniques, change crop production to livestock keeping, and possibly migrate to urban centers. Lack of climate change education, low access to credit and agricultural inputs are some militating factors crippling the farmers’ effort to adapt to climate change.

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The North Atlantic Ocean as a Modulator of Vegetation Greening/Browning in the Northern High Latitudes?

10.5194/egusphere-egu21-15595 ◽

2021 ◽

Author(s):

Leonard F. Borchert ◽

Alexander J. Winkler

Keyword(s):

Climate Variability ◽

North Atlantic ◽

North Atlantic Ocean ◽

Internal Variability ◽

Dominant Mode ◽

High Latitudes ◽

Model Simulations ◽

Internal Climate Variability ◽

The North ◽

The North Atlantic

Vegetation in the northern high latitudes shows a characteristic pattern of persistent changes as documented by multi-decadal satellite observations. The prevailing explanation that these mainly increasing trends (greening) are a consequence of external CO2 forcing, i.e., due to the ubiquitous effect of CO2-induced fertilization and/or warming of temperature-limited ecosystems, however does not explain why some areas also show decreasing trends of vegetation cover (browning). We propose here to consider the dominant mode of multi-decadal internal climate variability in the north Atlantic region, the Atlantic Multidecadal Variability (AMV), as the missing link in the explanation of greening and browning trend patterns in the northern high latitudes. Such a link would also imply potential for decadal predictions of ecosystem changes in the northern high latitudes.An analysis of observational and reanalysis data sets for the period 1979-2019 shows that locations characterized by greening trends largely coincide with warming summer temperature and increasing precipitation. Wherever either cooling or decreasing precipitation occurs, browning trends are observed over this period. These precipitation and temperature patterns are significantly correlated with a North Atlantic sea surface temperature index that represents the AMV signal, indicating its role in modulating greening/browning trend patterns in the northern high latitudes.Using two large ensembles of coupled Earth system model simulations (100 members of MPI-ESM-LR Grand Ensemble and 32 members of the IPSL-CM6A-LR Large Ensemble), we separate the greening/browning pattern caused by external CO2 forcing from that caused by internal climate variability associated with the AMV. These sets of model simulations enable a clean separation of the externally forced signal from internal variability. While the greening and browning patterns in the simulations do not agree with observations in terms of magnitude and location, we find consistent internally generated greening/browning patterns in both models caused by changes in temperature and precipitation linked to the AMV signal. These greening/browning trend patterns are of the same magnitude as those caused by the external forcing alone. Our work therefore shows that internally-generated changes of vegetation in the northern lands, driven by AMV, are potentially as large as those caused by external CO2 forcing. We thus argue that the observed pattern of greening/browning in the northern high latitudes could originate from the combined effect of rising CO2 as well as the AMV.

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Climate Variability and Change in Bihar, India: Challenges and Opportunities for Sustainable Crop Production

Sustainability ◽

10.3390/su9111998 ◽

2017 ◽

Vol 9 (11) ◽

pp. 1998 ◽

Cited By ~ 11

Author(s):

Kindie Tesfaye ◽

Pramod Aggarwal ◽

Fasil Mequanint ◽

Paresh Shirsath ◽

Clare Stirling ◽

...

Keyword(s):

Climate Variability ◽

Crop Production ◽

Climate Variability And Change ◽

Sustainable Crop Production ◽

Challenges And Opportunities

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CLIMATE VARIABILITY AND CHANGE: FARMER PERCEPTIONS AND UNDERSTANDING OF INTRA-SEASONAL VARIABILITY IN RAINFALL AND ASSOCIATED RISK IN SEMI-ARID KENYA

Experimental Agriculture ◽

10.1017/s0014479710000918 ◽

2011 ◽

Vol 47 (2) ◽

pp. 267-291 ◽

Cited By ~ 91

Author(s):

K. P. C. RAO ◽

W. G. NDEGWA ◽

K. KIZITO ◽

A. OYOO

Keyword(s):

Climate Variability ◽

Crop Production ◽

Smallholder Farmers ◽

Crop Productivity ◽

General Tendency ◽

Climate Variability And Change ◽

Negative Impacts ◽

Probabilistic Nature ◽

Semi Arid

SUMMARYThis study examines farmers’ perceptions of short- and long-term variability in climate, their ability to discern trends in climate and how the perceived trends converge with actual weather observations in five districts of Eastern Province in Kenya where the climate is semi-arid with high intra- and inter-annual variability in rainfall. Field surveys to elicit farmers’ perceptions about climate variability and change were conducted in Machakos, Makueni, Kitui, Mwingi and Mutomo districts. Long-term rainfall records from five meteorological stations within a 10 km radius from the survey locations were obtained from the Kenya Meteorological Department and were analysed to compare with farmers’ observations. Farmers’ responses indicate that they are well aware of the general climate in their location, its variability, the probabilistic nature of the variability and the impacts of this variability on crop production. However, their ability to synthesize the knowledge they have gained from their observations and discern long-term trends in the probabilistic distribution of seasonal conditions is more subjective, mainly due to the compounding interactions between climate and other factors such as soil fertility, soil water and land use change that determine the climate's overall influence on crop productivity. There is a general tendency among the farmers to give greater weight to negative impacts leading to higher risk perception. In relation to long-term changes in the climate, farmer observations in our study that rainfall patterns are changing corroborated well with reported perceptions from other places across the African continent but were not supported by the observed trends in rainfall data from the five study locations. The main implication of our findings is the need to be aware of and account for the risk during the development and promotion of technologies involving significant investments by smallholder farmers and exercise caution in interpreting farmers’ perceptions about long-term climate variability and change.

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Future Nuisance Flooding in Norfolk, VA, From Astronomical Tides and Annual to Decadal Internal Climate Variability

Geophysical Research Letters ◽

10.1029/2018gl079572 ◽

2018 ◽

Vol 45 (22) ◽

pp. 12,432-12,439 ◽

Cited By ~ 6

Author(s):

A. G. Burgos ◽

B. D. Hamlington ◽

P. R. Thompson ◽

R. D. Ray

Keyword(s):

Climate Variability ◽

Internal Climate Variability

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Influence of internal climate variability on Indian Ocean Dipole properties

Scientific Reports ◽

10.1038/s41598-018-31842-3 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 5

Author(s):

Benjamin Ng ◽

Wenju Cai ◽

Tim Cowan ◽

Daohua Bi

Keyword(s):

Indian Ocean ◽

Climate Variability ◽

Indian Ocean Dipole ◽

Internal Climate Variability

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Interhemispheric asymmetry of climate change projections of boreal winter surface winds in CanESM5 large ensemble simulations

10.21203/rs.3.rs-476108/v1 ◽

2021 ◽

Author(s):

Bin Yu ◽

Xuebin Zhang ◽

Guilong Li ◽

Wei Yu

Keyword(s):

Climate Variability ◽

Wind Power ◽

Atmospheric Circulation ◽

Large Scale ◽

Boreal Winter ◽

Interhemispheric Asymmetry ◽

Large Ensemble ◽

Internal Climate Variability ◽

Climate Simulations ◽

Extreme Wind

Abstract A recent study of future changes in global wind power using an ensemble of ten CMIP5 climate simulations indicated an interhemispheric asymmetry of wind power changes over the 21st century, featured by power decreases across the Northern Hemisphere mid-latitudes and increases across the tropics and subtropics of the Southern Hemisphere. Here we analyze future global projections of surface mean and extreme winds by means of a single-model initial-condition 50-member ensemble of climate simulations generated with CanESM5, the Canadian model participated in CMIP6. We analyze the ensemble mean and spread of boreal winter mean and extreme wind trends over the next half-century (2021-2070) and explore the contribution of internal climate variability to these trends. Surface wind speed is projected to mostly decrease in northern mid-low latitudes and southern mid-latitudes and increase in northern high latitudes and southern tropical and subtropical regions, with considerable regional variations. Large ensemble spreads are apparent, especially with remarkable differences over northern parts of South America and northern Russia. The interhemispheric asymmetry of wind projections is found in most ensemble members, and can be related to large-scale changes in surface temperature and atmospheric circulation. The extreme wind has similar structure of future projections, whereas its reductions tend to be more consistent over northern mid-latitudes. The projected mean and extreme wind changes are attributed to changes in both externally anthropogenic forced and internal climate variability generated components. The spread in wind projections is partially due to large-scale atmospheric circulation variability.

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Uncertainty in the future change of extreme precipitation over the Rhine basin: the role of internal climate variability

Climate Dynamics ◽

10.1007/s00382-014-2312-4 ◽

2014 ◽

Vol 44 (7-8) ◽

pp. 1789-1800 ◽

Cited By ~ 13

Author(s):

S. C. van Pelt ◽

J. J. Beersma ◽

T. A. Buishand ◽

B. J. J. M. van den Hurk ◽

J. Schellekens

Keyword(s):

Climate Variability ◽

Extreme Precipitation ◽

Future Change ◽

Internal Climate Variability ◽

Rhine Basin ◽

The Future

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Alternate history: A synthetic ensemble of ocean chlorophyll concentrations

10.5194/egusphere-egu21-1375 ◽

2021 ◽

Author(s):

Geneviève Elsworth ◽

Nicole Lovenduski ◽

Karen McKinnon

Keyword(s):

Climate Variability ◽

Internal Variability ◽

Ensemble Member ◽

Global Ocean ◽

Large Ensemble ◽

Internal Climate Variability ◽

Surface Ocean ◽

Large Ensembles ◽

Long Term Trends

Internal climate variability plays an important role in the abundance and distribution of phytoplankton in the global ocean. Previous studies using large ensembles of Earth system models (ESMs) have demonstrated their utility in the study of marine phytoplankton variability. These ESM large ensembles simulate the evolution of multiple alternate realities, each with a different phasing of internal climate variability. However, ESMs may not accurately represent real world variability as recorded via satellite and in situ observations of ocean chlorophyll over the past few decades. Observational records of surface ocean chlorophyll equate to a single ensemble member in the large ensemble framework, and this can cloud the interpretation of long-term trends: are they externally forced, caused by the phasing of internal variability, or both? Here, we use a novel statistical emulation technique to place the observational record of surface ocean chlorophyll into the large ensemble framework. Much like a large initial condition ensemble generated with an ESM, the resulting synthetic ensemble represents multiple possible evolutions of ocean chlorophyll concentration, each with a different phasing of internal climate variability. We further demonstrate the validity of our statistical approach by recreating a ESM ensemble of chlorophyll using only a single ESM ensemble member. We use the synthetic ensemble to explore the interpretation of long-term trends in the presence of internal variability. Our results suggest the potential to explore this approach for other ocean biogeochemical variables.

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